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Human Migration and Population

Learn why people migrate (push and pull factors), major migrations, urbanization and population change, and how to read population pyramids and flow maps.

Practice this skill 20 min Human migration Leer en español
Key idea

What you'll learn

In plain words: people move to find a better or safer life, and those moves change both places — the one they leave and the one they join.

People have always moved. They move to find food, escape danger, or build a better life. Migration has shaped every country. This is especially true of the United States. The U.S. was built by three groups:

  • immigrants who chose to come;
  • enslaved people brought by force;
  • Native peoples who were here first.

In this lesson you will learn:

  • the vocabulary of migration: immigrant, emigrant, refugee, push and pull factors;
  • the major types of migration: voluntary and forced, internal and international;
  • key migrations in U.S. history, from Ellis Island to the Great Migration;
  • urbanization and population growth, and how to measure them;
  • how to read population pyramids, flow maps, and line graphs of demographic data.

How it shows up on the GED: this is one of the most data-heavy geography topics. Expect a population pyramid, a line graph of urban population, or a flow map with arrows. You may also read a passage or primary source about immigration. Questions ask you to:

  • classify push and pull factors;
  • read values accurately and calculate a change;
  • compare two sources;
  • predict what a population will look like in the future.
Words to know

Key terms

  • migration — moving from one place to another to live (a family moves from Ohio to Texas).
  • emigrate / emigrant — to leave your home country / a person who leaves ("e" for exit).
  • immigrate / immigrant — to enter a new country to live / a person who enters ("i" for in).
  • internal migration — moving within the same country (the Great Migration from the South to the North).
  • international migration — moving from one country to another.
  • push factor — a problem that drives people away from home (war, drought, no jobs).
  • pull factor — an attraction that draws people to a new place (jobs, safety, family already there).
  • voluntary migration — people choose to move.
  • forced migration — people are made to move (the Atlantic slave trade; the Trail of Tears).
  • refugee — a person who flees war, violence, or persecution and crosses an international border.
  • internally displaced person (IDP) — someone forced from home who stays inside their own country.
  • chain migration — migrants follow relatives or neighbors who moved before them.
  • urbanization — the growth of the share of people living in cities.
  • suburbanization — movement from cities to surrounding suburbs.
  • birth rate / death rate — births or deaths per 1,000 people per year.
  • natural increase — birth rate minus death rate (growth without migration).
  • net migration — immigrants minus emigrants (people in minus people out).
  • population pyramid — a graph of a population by age group and sex.
  • demographics — statistics about a population (age, sex, income, education).

All Social Studies words in the glossary

Why people move: push and pull factors

In plain words: people move because something at home pushes them out and something elsewhere pulls them in.

Think about changing jobs. Maybe your boss cut your hours (a push). Maybe another company offers more pay (a pull). Most moves have both. Almost every migration combines push factors at home and pull factors elsewhere. They fall into four groups:

TypePush examplesPull examples
EconomicUnemployment, poverty, crop failureJobs, higher wages, land
PoliticalWar, persecution, no voting rightsFreedom, safety, democracy
SocialDiscrimination, poor schoolsFamily already there, good schools
EnvironmentalDrought, floods, natural disastersFertile land, better climate

Obstacles can stand in the way. Examples are distance, cost, borders, immigration laws, and not knowing the language. Chain migration helps people overcome them. Relatives who moved first send letters, make phone calls, and send money. That makes the trip easier and less risky.

Push and pull migration diagram. On the left is the home place, with red push factors such as war, drought and no jobs pushing people out. On the right is the destination, with green pull factors such as jobs, safety and family already there drawing people in. A blue arrow labeled migration goes from home to the destination and passes a dashed barrier of obstacles: distance, cost, borders and laws, and language. A dashed arrow from the destination back to home shows chain migration: relatives send letters, calls and money that make the trip easier. HOME PUSH factors war drought no jobs DESTINATION PULL factors jobs safety family already there migration Obstacles distance, cost, borders and laws, language pushed out pulled in chain migration: letters, calls, money from relatives

Example: Ireland's Great Famine (1845–1852) was caused by a disease that destroyed the potato crop. It killed about a million people. It pushed more than a million to emigrate, many to U.S. cities like Boston and New York.

  • Famine = environmental and economic push.
  • Jobs and relatives in America = pull.

Major migrations in U.S. and world history

In plain words: some people chose to come to the U.S., some were forced to come or to move, and many moved within the country.

Two-by-two chart of migration types. Columns: voluntary (people choose to move) and forced (people are made to move). Rows: internal (within one country) and international (between countries). Voluntary internal: the Great Migration, about 1910 to 1970, and westward expansion. Forced internal: the Trail of Tears, 1838 to 1839. Voluntary international: about 20 million new immigrants, 1880 to 1920, through stations like Ellis Island. Forced international: the Atlantic slave trade, 1500s to 1800s; refugees fleeing war also cross borders, for example from Syria after 2011. Voluntary people choose to move Forced people are made to move Internal within one country International between countries Great Migration (about 1910–1970) Westward expansion (1800s) Trail of Tears (1838–1839) Native nations forced west "New immigrants" 1880–1920, through stations like Ellis Island Atlantic slave trade (1500s–1800s) Refugees fleeing war (e.g. Syria, 2011–)

Forced migration

  • The Atlantic slave trade (1500s–1800s): about 12 million Africans were forced across the Atlantic. Roughly 400,000 were brought directly to North America.
  • Indian Removal: Congress passed the Indian Removal Act in 1830. After that, the U.S. government forced Cherokee and other Native nations west. Thousands died on the Trail of Tears (1838–1839).

Waves of immigration to the United States

  • 1840s–1850s: Irish (fleeing famine) and Germans (fleeing hard times and political unrest).
  • 1880–1920: more than 20 million "new immigrants" arrived. Many came from Southern and Eastern Europe (Italy, Poland, Russia). They entered through stations like Ellis Island (opened 1892). Many Chinese came to the West Coast earlier. But the Chinese Exclusion Act (1882) banned Chinese laborers. It was the first major U.S. law to bar a group by nationality.
  • 1924: the Immigration Act set national-origin quotas — fixed limits for each country. They sharply limited immigration from Southern and Eastern Europe and barred most Asians.
  • 1965: the Immigration and Nationality Act ended the national-origin quotas. Immigration from Latin America and Asia grew.

Internal migration

  • Westward expansion in the 1800s.
  • The Great Migration (about 1910–1970): roughly 6 million African Americans left the rural South for northern and western cities. Pushes: Jim Crow segregation, violence, and the boll weevil, an insect that destroyed cotton crops. Pulls: factory jobs and higher wages.
  • The Dust Bowl (1930s): hundreds of thousands left the southern Plains, many for California.
Timeline from 1820 to 1980 of key U.S. migrations and laws, one row each. Red bars or dots are forced migration: Indian Removal Act, 1830; Trail of Tears, 1838 to 1839. Blue bars are immigration waves: Irish famine emigration, 1845 to 1852; new immigrants, 1880 to 1920. Green bars are internal migration: Great Migration, about 1910 to 1970; Dust Bowl migration, 1930s. Black dots are laws or events: Chinese Exclusion Act, 1882; Ellis Island opens, 1892; national-origin quotas, 1924; Immigration and Nationality Act ends quotas, 1965. 1820 1840 1860 1880 1900 1920 1940 1960 1980 Indian Removal Act 1830 Trail of Tears 1838–1839 Irish famine emigration 1845–1852 Chinese Exclusion Act 1882 "New immigrants" wave 1880–1920 Ellis Island opens 1892 Great Migration about 1910–1970 National-origin quotas 1924 Dust Bowl migration 1930s Quotas ended (1965 Act) 1965 forced migration immigration wave internal migration law or event

Refugees today: wars and persecution have created millions of refugees. One example is Syria's civil war, which began in 2011. Most refugees stay in neighboring countries.

Urbanization and population growth

Line graph of the percent of the U.S. population living in urban areas by census year: 1790: 5.1%; 1850: 15.4%; 1880: 28.2%; 1900: 39.6%; 1920: 51.2%; 1950: 64.0%; 1970: 73.6%; 2000: 79.0%; 2020: 80.0%. A dashed line marks 50%. The line first rises above 50% in 1920. Source: U.S. Census Bureau (rounded). 0% 20% 40% 60% 80% 100% 50% (half the population) 1800 1850 1900 1950 2000 1790: 5.1% 1850: 15.4% 1880: 28.2% 1900: 39.6% 1920: 51.2% 1950: 64.0% 1970: 73.6% 2000: 79.0% 2020: 80.0% Census year Percent living in urban areas Share of the U.S. Population Living in Urban Areas, 1790–2020 Source: U.S. Census Bureau (rounded)

In plain words: over time, more and more people moved from farms to cities, and the world's population grew very fast.

Urbanization is the shift of people from farms and villages to cities. It speeds up when two things happen. Industry creates city jobs. And farm machines reduce the need for farm workers.

  • In 1790, only about 5% of Americans lived in urban areas.
  • By 1920, more than half did (51.2%). It was the first time in U.S. history.
  • Today about 80% of Americans live in urban areas. After World War II, many families also moved to suburbs. Cars, highways, and new home loans helped them.
  • Worldwide, more than half of all people have lived in cities since about 2007. The fastest urban growth is now in Africa and Asia.

Population growth depends on births, deaths, and migration. Think of a bank account: money comes in, money goes out.

\text{population change} = (\text{births} - \text{deaths}) + (\text{immigrants} - \text{emigrants})
Diagram of population change like a bank account. A central box labeled Population has two green arrows coming in, births and immigrants, and two red arrows going out, deaths and emigrants. Births minus deaths is the natural increase. Immigrants minus emigrants is net migration. Population change equals natural increase plus net migration. POPULATION like a bank account Births (+) Immigrants (+) Deaths (−) Emigrants (−) in out births − deaths = natural increase immigrants − emigrants = net migration population change = natural increase + net migration

World population reached about 1 billion around 1800. It passed 8 billion in 2022. Better food, clean water, and medicine lowered death rates. Birth rates fell much later. So for a long time, far more people were born than died, and population boomed. Geographers call this pattern the demographic transition:

  1. high birth and death rates;
  2. falling death rates (rapid growth);
  3. falling birth rates;
  4. low birth and death rates (slow growth or decline).
Illustrative line graph of the four-stage demographic transition, not real data. The vertical axis is rate per 1,000 people per year, from 0 to 50. Stage 1: birth and death rates are both high, about 40 and 38, so little growth. Stage 2: death rate falls to about 12 while the birth rate stays near 38, rapid growth. Stage 3: the birth rate falls to about 15. Stage 4: both are low, about 12 and 11, slow growth. The shaded gap between the lines is natural increase. 0 10 20 30 40 50 Stage 1 little growth Stage 2 rapid growth Stage 3 growth slows Stage 4 slow growth birth rate death rate natural increase rate per 1,000 people per year Illustrative shape only (not real data).
Line graph of world population milestones, approximate: 1 billion about 1800, 2 billion 1927, 3 billion 1960, 4 billion 1974, 5 billion 1987, 6 billion 1999, 7 billion 2011, and 8 billion 2022. It took over 100 years to add the second billion but only about 12 years for each recent billion. 0 1 2 3 4 5 6 7 8 9 1800 1840 1880 1920 1960 2000 2040 1800: 1 billion 1927: 2 billion 1960: 3 billion 2022: 8 billion world population (billions) World population milestones (approximate) 1 billion to 2 billion: about 127 years. Each recent billion: about 12 years.

Example: A country's birth rate is 30 per 1,000. Its death rate is 10 per 1,000. Its natural increase is 20 per 1,000, or 2% per year. That is fast growth.

Reading population pyramids and flow maps

Two population pyramids, population in millions by 10-year age group, males on the left (blue) and females on the right (green), youngest at the bottom. Country A: 0–9: 5.0 male, 4.8 female; 10–19: 4.4 male, 4.3 female; 20–29: 3.8 male, 3.8 female; 30–39: 3.0 male, 3.1 female; 40–49: 2.2 male, 2.3 female; 50–59: 1.5 male, 1.6 female; 60–69: 0.9 male, 1.0 female; 70+: 0.5 male, 0.7 female. Country A is widest at the base and narrows steadily toward the top. Country B: 0–9: 2.0 male, 1.9 female; 10–19: 2.3 male, 2.2 female; 20–29: 2.8 male, 2.7 female; 30–39: 3.3 male, 3.2 female; 40–49: 3.8 male, 3.9 female; 50–59: 3.3 male, 3.4 female; 60–69: 2.7 male, 3.0 female; 70+: 2.0 male, 2.8 female. Country B is narrow at the base and widest in the 40–49 age group. Country A Male Female 70+ 60–69 50–59 40–49 30–39 20–29 10–19 0–9 0 0 2 2 4 4 6 6 Population (millions) Country B Male Female 70+ 60–69 50–59 40–49 30–39 20–29 10–19 0–9 0 0 2 2 4 4 6 6 Population (millions) Population Pyramids of Two Countries (fictional data)

In plain words: a population pyramid shows how many people are young or old; a flow map shows where people moved.

Population pyramids show the number (or percent) of people in each age group. Males are on one side and females on the other. The youngest are at the bottom.

ShapeWhat it looks likeWhat it means
ExpansiveWide base, narrow top (a true pyramid)High birth rate, young and growing population; needs schools and jobs
StationaryFairly even bars, like a columnBirth and death rates about equal; slow or no growth
ConstrictiveNarrow base, bulge in the middle or topLow birth rate, aging population; future worker shortages and high elder-care costs
Three illustrative population pyramid shapes, not real data, each with males on the left, females on the right, and age groups from 0-9 at the bottom to 70+ at the top. Expansive: a wide base and narrow top, meaning a high birth rate and a young, growing population. Stationary: bars of nearly equal width like a column, meaning slow or no growth. Constrictive: a narrow base with a bulge in the middle and top, meaning a low birth rate and an aging population. Expansive young, growing Males Females Stationary slow or no growth Males Females Constrictive aging, low births Males Females 0–9 10–19 20–29 30–39 40–49 50–59 60–69 70+ Illustrative shapes (not real data). Youngest at the bottom; current births show in the bottom bar.

To predict the future, imagine every bar sliding up one row per ten years. A big group of 40-year-olds today will be a big group of 70-year-olds in 30 years.

Flow maps use arrows to show movement.

  • The arrow's direction shows where people went.
  • Its width (or a number label) shows how many.
  • To find a place's net migration, add the arrows pointing in. Then subtract the arrows pointing out.
  • Ignore arrows that don't touch that place.

Example: On the Novara flow map, North Hills sends 120,000 people to Valdor and receives none. So North Hills' net migration is −120,000, a population loss.

Formula

Calculations you may need

Net migration:

\text{net migration} = \text{immigrants (in)} - \text{emigrants (out)}

Natural increase:

\text{rate of natural increase (\%)} = \dfrac{\text{birth rate} - \text{death rate}}{10}

(when rates are given per 1,000 people)

Percentage-point change vs. percent change:

  • Percentage points: new percent − old percent (15.4% → 39.6% is a 24.2-point increase).
  • Percent change: \dfrac{\text{new} - \text{old}}{\text{old}} \times 100 (a city growing from 50,000 to 65,000 grew by 30%).

The Social Studies test has no formula sheet; learn them. Use the on-screen calculator for the arithmetic.

Worked example

Example 1: Reading a population pyramid

Two population pyramids, population in millions by 10-year age group, males on the left (blue) and females on the right (green), youngest at the bottom. Country A: 0–9: 5.0 male, 4.8 female; 10–19: 4.4 male, 4.3 female; 20–29: 3.8 male, 3.8 female; 30–39: 3.0 male, 3.1 female; 40–49: 2.2 male, 2.3 female; 50–59: 1.5 male, 1.6 female; 60–69: 0.9 male, 1.0 female; 70+: 0.5 male, 0.7 female. Country A is widest at the base and narrows steadily toward the top. Country B: 0–9: 2.0 male, 1.9 female; 10–19: 2.3 male, 2.2 female; 20–29: 2.8 male, 2.7 female; 30–39: 3.3 male, 3.2 female; 40–49: 3.8 male, 3.9 female; 50–59: 3.3 male, 3.4 female; 60–69: 2.7 male, 3.0 female; 70+: 2.0 male, 2.8 female. Country B is narrow at the base and widest in the 40–49 age group. Country A Male Female 70+ 60–69 50–59 40–49 30–39 20–29 10–19 0–9 0 0 2 2 4 4 6 6 Population (millions) Country B Male Female 70+ 60–69 50–59 40–49 30–39 20–29 10–19 0–9 0 0 2 2 4 4 6 6 Population (millions) Population Pyramids of Two Countries (fictional data)

Use the pyramids for Country A and Country B.

Question: In Country A, about how many people (males and females together) are aged 70 or older?

Think aloud:

  1. "Country A is the left pyramid. The 70+ bar is at the top."
  2. "Male side: 0.5 million. Female side: 0.7 million."
  3. "Add them: 0.5 + 0.7 = 1.2 million."
  4. "That's tiny compared with the 0–9 group (9.8 million). This confirms Country A is a young, expansive population."

Answer: about 1.2 million. Always add both sides when a question asks about everyone in an age group.

Worked example

Example 2: Interpreting a demographic line graph

Line graph of the percent of the U.S. population living in urban areas by census year: 1790: 5.1%; 1850: 15.4%; 1880: 28.2%; 1900: 39.6%; 1920: 51.2%; 1950: 64.0%; 1970: 73.6%; 2000: 79.0%; 2020: 80.0%. A dashed line marks 50%. The line first rises above 50% in 1920. Source: U.S. Census Bureau (rounded). 0% 20% 40% 60% 80% 100% 50% (half the population) 1800 1850 1900 1950 2000 1790: 5.1% 1850: 15.4% 1880: 28.2% 1900: 39.6% 1920: 51.2% 1950: 64.0% 1970: 73.6% 2000: 79.0% 2020: 80.0% Census year Percent living in urban areas Share of the U.S. Population Living in Urban Areas, 1790–2020 Source: U.S. Census Bureau (rounded)

Use the urban population graph.

Question: Between which two census years shown did the urban share grow the most per decade? A. 1790–1850 B. 1900–1920 C. 1970–2000 D. 2000–2020

Think aloud:

  1. "I need growth per decade, because the intervals have different lengths."
  2. "A: 5.1 → 15.4 = 10.3 points over 6 decades ≈ 1.7 per decade."
  3. "B: 39.6 → 51.2 = 11.6 points over 2 decades = 5.8 per decade."
  4. "C: 73.6 → 79.0 = 5.4 points over 3 decades = 1.8 per decade. D: 79.0 → 80.0 = 1.0 over 2 decades = 0.5."

Answer: B, 1900–1920, the era of factories and mass immigration. Watch out: uneven time spans can trick you. A long period can look like fast growth.

Worked example

Example 3: A flow map

Schematic flow map of the fictional country Novara, 2010–2020. Arrows show migrants moving: from North Hills (rural) to Valdor, the capital, 120,000; from East Plains (rural) to Valdor, 85,000; from South Coast (rural) to Valdor, 45,000; from East Plains to the city of Port Lira, 40,000; and from Valdor to other countries, 30,000. Wider arrows mean more people. North Hills (rural province) East Plains (rural province) South Coast (rural province) Valdor (capital) Port Lira Other countries 120,000 85,000 45,000 40,000 30,000 Migration in Novara, 2010–2020 (fictional data) Arrow = movement of migrants; wider arrow = more people. Numbers are migrants who moved, 2010–2020.

Use the Novara flow map.

Question: What was the net migration for the East Plains province?

Think aloud:

  1. "Find every arrow touching East Plains."
  2. "Out: 85,000 to Valdor and 40,000 to Port Lira, so 125,000 left."
  3. "In: no arrows point into East Plains."
  4. "Net = in − out = 0 − 125,000 = −125,000."
Net migration tally for East Plains province in the fictional country Novara. Two arrows go out of East Plains: 85,000 people to Valdor and 40,000 people to Port Lira. No arrows come in. In: 0. Out: 85,000 plus 40,000 equals 125,000. Net migration equals in minus out: 0 minus 125,000 equals negative 125,000. East Plains rural province Valdor capital city Port Lira city out: 85,000 out: 40,000 in: 0 (no arrows in) Net = in − out = 0 − (85,000 + 40,000) = −125,000 Novara (fictional): arrows touching East Plains

Answer: −125,000. The province lost population to cities. This is rural-to-urban migration. A negative net migration means more people left than arrived.

Worked example

Example 4: Push and pull in a primary source

In 1883, Emma Lazarus wrote that the Statue of Liberty says, "Give me your tired, your poor, / Your huddled masses yearning to breathe free."

Question: Which pull factor does this poem emphasize? A. High wages in factories B. Freedom and refuge for the poor and oppressed C. Cheap farmland in the West D. Family members already in America

Think aloud:

  1. "'Yearning to breathe free' points to freedom."
  2. "'Tired,' 'poor,' 'huddled masses' — the poem offers refuge to people who are suffering."
  3. "The poem never mentions wages, farmland, or relatives, so A, C, and D bring in outside ideas."

Answer: B. Stick to what the source actually says, even if other answers are true facts about immigration.

Common mistake

Common mistakes

  • Mixing up immigrant and emigrant. Wrong: "People leaving Mexico are immigrants from Mexico's point of view." Right: for Mexico, they are emigrants (they exit); for the U.S., they are immigrants (they come in). Check whose point of view the question uses.
  • Calling a push factor a pull factor. Wrong: "Drought is a pull factor." Right: drought at home pushes people out; jobs elsewhere pull them in.
  • Calling every displaced person a refugee. Wrong: "People who fled to another part of their own country are refugees." Right: they are internally displaced. Refugees cross an international border.
  • Reading a pyramid's middle as the birth rate. Wrong: "Country B's wide middle means many births." Right: current births show in the bottom bar.
  • Confusing percentage points with percent change. Wrong: "15% to 40% is a 25% increase." Right: it is a 25-point increase, or about a 167% increase.
  • Counting unrelated arrows on a flow map. Wrong: adding the East Plains → Port Lira arrow to Valdor's total. Right: count only arrows that touch the place asked about.
Test strategy

GED strategy

  • Label the graph first: title, axes, units (millions? percent?), and which side or color is which.
  • For pyramids, check where the youngest group is and add both sexes when the question says "people."
  • For flow maps, mark arrows in (+) and out (−) on your note board before calculating.
  • For push/pull questions, ask "Is this describing the home place or the destination?"
  • For definitions in the stem (like the refugee definition), test every choice against every condition.
  • For paired sources, label each: type (law, poem, speech), attitude (welcoming, restrictive), and scope (who it covers).
  • Use the calculator for differences and percents, but estimate first so you can spot a keying error.
  • Pace: data questions take about 90–120 seconds; flag and return if needed.

Check yourself

Human migration
Ana's Journey

(1) Ana Ruiz grew up in a small farming village. For three years in a row, too little rain fell, and her family's corn crop failed. The village school closed when its only teacher left, and gangs began demanding money from local shop owners.

(2) Ana's cousin had moved to a city in another country five years earlier. He wrote that a food-processing plant there was hiring workers and paid about four times what Ana could earn at home. He also said the city had good public schools for her two children.

(3) In 2019, Ana and her children left their village and moved to that city, where they joined her cousin's family. Ana began working at the plant, and her children started school the following month.

Which detail from the passage is a pull factor that drew Ana to her new city?

Answer choices
Hint

Push factors are problems at home. Pull factors are attractions in the new place.

Check yourself

Human migration
Ana's Journey

(1) Ana Ruiz grew up in a small farming village. For three years in a row, too little rain fell, and her family's corn crop failed. The village school closed when its only teacher left, and gangs began demanding money from local shop owners.

(2) Ana's cousin had moved to a city in another country five years earlier. He wrote that a food-processing plant there was hiring workers and paid about four times what Ana could earn at home. He also said the city had good public schools for her two children.

(3) In 2019, Ana and her children left their village and moved to that city, where they joined her cousin's family. Ana began working at the plant, and her children started school the following month.

From the point of view of the country where Ana was born, Ana is best described as

Answer choices
Hint

*E*migrate = *e*xit your country. *I*mmigrate = come *i*nto a new country.

Summary

  • Migration results from push factors at home and pull factors elsewhere: economic, political, social, and environmental.
  • An emigrant leaves a country. An immigrant enters one. Refugees flee war, violence, or persecution across a border. IDPs stay inside their country.
  • Key U.S. migrations: the forced slave trade and Indian Removal; European waves (Irish, Germans, and 1880–1920 "new immigrants"); Chinese exclusion (1882); quotas (1924) and their end (1965); the Great Migration (about 1910–1970).
  • The U.S. became majority urban by 1920. It is about 80% urban today. World population passed 8 billion in 2022.
  • Population pyramids: a wide base means high births and growth; a narrow base means an aging population.
  • Net migration = in − out; percentage points = new % − old %; percent change = change ÷ original × 100.
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