4.4G: Changes and Continuities in Slavery 1450 to 1750


AP Theme

Social Interactions and Organization

Learning Objective 4G

Explain changes and continuities in systems of slavery in the period from 1450 to 1750.

Historical Development 1

Traditional forms of slavery continued, including incorporating slaves into households and exporting slaves to the Mediterranean and the Indian Oceans regions.

Historical Development 2

The growth of the plantation economy increased the demand for slaves in the Americas, leading to significant demographic changes.

Key ideas

Civilizations throughout history have used slave labor. The transatlantic slave trade was a brutal expansion of the preexisting African slave trade. The increased demand for enslaved Africans in the Americas resulted from the growth of cash-crop agriculture.

The slave trade created large populations of African ancestry and mixed-race people throughout the Americas.  In Africa, population loss resulted in worsening economic conditions.


The African Slave Trade

Main idea

Civilizations throughout history have used slave labor. The transatlantic slave trade was a brutal expansion of the preexisting African slave trade. The increased demand for enslaved Africans in the Americas resulted from the growth of cash-crop agriculture.

The evils of slavery have been a part of human societies as long back as we have historical records. Societies have enslaved people from various populations throughout history. For thousands of years, two regions—Africa and Eastern Europe—provided many of the world’s enslaved peoples to slave markets.

The transatlantic slave trade

While Africa has long been a source of enslaved people, the transatlantic slave trade expanded the horrors of African slavery beyond anything the continent had previously experienced.

How Africans became enslaved: The vast tragedy of the transatlantic slave trade began with the capture of human beings in Africa. African leaders sold Africans to European slave traders for the economic benefits that the slave trade provided. Those sold by African leaders often came from conquered societies or people captured from neighboring tribes. Leaders also sold poor people and criminals from their own communities. Captives went to barracoons (slave castles), where they waited to be forced from their homelands and families, never to return.

The Middle Passage: Enslaved peoples journeyed to the Americas through the Middle Passage—named this because it was the middle part of the journey after capture and before being sold in the Americas. The journey was horrendous and lasted six weeks. During that time, to prevent rebellion and pack more enslaved peoples onto the ship, slave traders tied their captives down with chains onto bunk bed-type layers. With just a few inches between layers, there was no room to move or sit upright. Ten to fifteen percent of African captives died in these torturous conditions before making it to the Americas.

Plantation agriculture led to the transatlantic slave trade: Most enslaved Africans worked on large commercial agricultural plantations that produced cash crops like sugar and tobacco. Around eighty percent of enslaved people from Africa arrived in the sugar-producing colonies in the Caribbean and the east coast of Brazil, where death rates from disease and overwork in a tropical climate resulted in high death rates among enslaved people. About ten percent came to the British colonies in North America to work on tobacco plantations in the Southern colonies.

Destination of Enslaved Africans in the Americas

Changes in systems of slavery: All slavery throughout history violates modern understanding of human rights. However, slavery in the Americas was a uniquely ruthless form of servitude. Enslaved people were no longer just property. Slave laws stripped them of all personhood and reduced them to positions no better than animals.

Traditional slavery before 1450
Transatlantic slavery after 1450
Enslaved people often integrated into owners’ households and communities.
Enslaved persons were not commonly integrated into households and communities.
Enslaved women who performed household labor were preferred.
Enslaved men for difficult plantation work preferred.
Children did not always inherit the slave status of their parents.
Children nearly always inherited their parents’ slave status.
Certain enslaved people could achieve elite political or military status in some societies.
Systems of oppression kept the enslaved from achieving any political, economic, or social status.
Slavery was often associated with warfare and capture, not necessarily race.
Slavery became racialized and associated with blackness.

The African slave trade continued along older slave trading networks

Africa has a long history of slavery. Even after the start of the transatlantic slave trade along Africa’s west coast, slave traders in East Africa continued to sell enslaved Africans north into the Mediterranean and East into the Indian Ocean region. Many enslaved people ended up in the Middle East and India. The African slave trade peaked in the 19th century along the west and east African coasts.

The Atlantic Slave Trade Shaped Populations in the Americas and Africa

Main idea

The slave trade created large populations of African ancestry and mixed-race people throughout the Americas.  In Africa, population loss resulted in worsening economic conditions.

The trafficking of millions of enslaved Africans to the Americas changed the population demographics of continents on both sides of the Atlantic.

Demographic changes in the Americas

Enslaved Africans ended up in servitude across the Americas.

Significant demographic changes included Africans

  • Becoming the dominant ethnic and racial group
  • Developing a sizeable minority population
  • Mixing with non-Africans to create mixed-race communities

Africans in the Caribbean: On many Caribbean islands, enslaved Afro-Caribbeans outnumbered their European masters. With so few whites and indigenous populations decimated, Africans became the dominant group across many Caribbean islands. Most of these individuals trace their roots back to West Africa and descend from enslaved Africans brought to the region to work on sugarcane plantations.

  • In the French colony of Haiti, 93% of the population descended from enslaved Africans in 1790.
  • Africans also became the majority population on the island of Jamaica and today account for nearly 92% of the island’s population.
  • Minority and mixed-race African communities developed across other islands, such as Cuba and Puerto Rico. Afro-Cubans were 9.5% of the island’s people in 2016, while they were 12.5% of Puerto Rico’s population in 2016.

Africans in Spanish colonies in Latin and South America: Millions of enslaved Africans also found themselves in Spain’s Latin and South American colonies. At the height of Mexico’s use of slave labor, over 200,000 Africans worked in slave labor jobs. Significant African ancestry populations developed across the region. The number of people in modern Columbia identifying as either full or partial Afro-Columbian was nearly seven percent in the 2018 census. The number was just above seven percent in Ecuador’s 2010 census.  

Africans in Brazil: The highest number of enslaved Africans landed in Portuguese Brazil. In 1825, Africans accounted for nearly 50% of Brazil’s population. Racial mixing was common in Brazil and led to a large population of mixed-race children. Referred to as mulattoes, this group became a middle-status group in Brazilian society. Many held mid-level jobs, such as managers on plantations or skilled urban labor. Afro-Brazilians accounted for nearly 8% of Brazil’s population in the 2010 census. Just over 43% percent of Brazil’s population identifies as mixed race.

Africans in North America: The first enslaved people arrived in the British Virginia colony in 1619. Between 1626 and 1725, just over 7000 Africans were shipped to the colonies. The growth of plantation agricultural products like tobacco dramatically increased slave arrivals to around 275,000 between 1726 and 1825.

  • Strict racial segregation laws in the North American colonies led to less racial mixing than in the Caribbean and Latin and South America. As a result, a sizeable mixed-race population did not develop.
  • Separation was easier to enforce because Europeans in the British colonies often arrived with their families, leading to fewer sexual relationships between Europeans and Africans and natives. While in Brazil, for example, many European men initially came without wives or families, resulting in more interracial relationships.
Large mixed-race populations
Largely black African population
Majority white population
Latin American colonies
The Caribbean colonies
North American colonies

Demographic changes in Africa

Africa lost an estimated 12 million people from their population to the transatlantic slave trade. Such a significant population loss had devastating long-term effects on those who remained in Africa, as political instability and economic decline further limited Africa’s ability to replace lost people.

Direct demographic changes included:

Disruption of rural life

Scholars estimate that between 1701 and 1850, 77 percent of enslaved people shipped across the Atlantic (10.1 million) came from Africa's west coast—the modern countries of Togo, Benin, Nigeria, the Democratic Republic of Congo, Angola, and Ghana. Most captives came from smaller and weaker tribes further into Africa's interior. With their youngest and strongest men and women taken, many of these societies weakened and became easier targets for conquest by warlords who exploited regional populations.

Lack of social development

Powerful African rulers grew wealthy by selling captives to European traders. They did not focus on developing their societies because the slave trade was so lucrative. African states that sold enslaved people prospered initially but, over time, grew weaker as they failed to keep up with modern technology and production methods. By the 19th century, these once-powerful coastal trading kingdoms had weakened enough to be conquered by Europeans.

Increased poverty

African poverty increased in interior areas as population loss to slavery decreased production, and warlords exploited those that remained. Enriched by the slave trade, rural warlords and coastal rulers did not invest in social development projects, like roads, that would economically and socially develop economies and societies long-term.

Africa's percentage of the global population decreased:

Between the 16th and 19th centuries, Africa's share of the worldwide population fell. In 1600, Africa was 17 percent of the global population. By 1900, it had dropped to 8 percent. This remarkable drop resulted from the 12 million enslaved people shipped to the Americas and the countless numbers who died from increased poverty, warfare, and social instability caused by the trade.