Slave Voyage Database Investigations

Investigatory Data Analysis

March 13, 2023, 9:48 p.m.

Andrew Allio

Graduate Student

Lesson Plan

Downloadable Materials:  

Student Worksheet

Teacher's Guide

On-Site Teacher's Guide:

Overview & Background to Activity

This activity is to meant to familiarize students with the intra-American slave trade. Distinct from the more familiar transatlantic slave trade, the intra-American slave trade involved the transport and exchange of enslaved Africans between one port in the Americas to another. These voyages landed in ports as far South as Uruguay, and as far North as Canada. Massive numbers of enslaved Africans were brought to Brazil, the Spanish American mainland, and the United States. Most of the enslaved people moved were recent survivors of the Middle Passage (of the transatlantic slave trade.) These people were forced to endure further voyages that extended their dangerous journeys in captivity by weeks and months, and helped spread the institution of slavery throughout the Americas. While slavery obviously was/is a problem in the United States this database helps illustrate that slavery was a major issue throughout the entire hemisphere; nearly all of the Americas were involved with the slave trade.

The terminology used here may create some confusion for students. When talking about the intra-American slave trade, students may assume this means between cities and places within the United States of America. It is important to clarify that this term refers to American continents, both North and South as well as Caribbean islands. When referring to specific countries, use of the term The United States is preferred to minimize confusion for students.

The information in this activity focuses on the number of voyages between the Caribbean and mainland North America. By focusing on the number of voyages, students will be able to gain a greater sense of the scale of the slave trade. Some ships left ports with small numbers of enslaved Africans, which may cloud a student’s understanding of the massive number of slave ships arriving on American shores. Looking at the number of slave voyages will also help students understand where the hubs of the slave trade were. Barbados and Jamaica were major centers of the slave trade in the Caribbean partly because of the importance of sugar production to the colonial economy. Jamaica also became an important hub for its proximity to the Spanish American mainland, and Barbados due to its location as the first island stops when reaching the Caribbean from Africa. Enslaved people were taken to these islands from Africa by slave traders and then dispersed across the Americas. These enslaved Africans were separated from their families and loved ones, separated from their homeland and familiar languages, and violently forced to work on plantations throughout the Western Hemisphere.

The activity is divided into distinct parts that take students from a broad sweeping view of the slave trade, to a more detailed and specific look at data involving slave voyages. Students will begin by doing a basic skills check. This consists of a vocabulary check and a review of map and table interpretation skills. Once students complete this pre-activity, they will be directed to the Slave Voyages website. The first portion is centered around a timelapse that charts the movement of slave ships throughout the Western Hemisphere. Students will make inferences and attempt to draw conclusions from the big picture data that is shown on the map. In part II, students will investigate a line graph representing a timeline of the intra-American slave trade. Here they will use more specific data begin to evaluate some of their conclusions from the timelapse portion of the activity. In part III, students will then use a table to investigate pairings of American ports and the number of voyages between them.

This activity draws its information from the Slave Voyages project, an online database documenting the movement and records for more than 50,000 transatlantic and intra-American slaving expeditions and the transporting of millions of enslaved people. The website is free to use and hosts the open database, charts, maps, and additional lesson plans for K-12 classrooms.


Students will

  1. Become familiar with historical data and databases
  2. Interpret data points regarding the intra-American slave trade
  3. Extract and evaluate information using a variety of data visualizations

Suggested Grade & Course

This activity is designed for a middle school social studies class with access to computers. This can be used as a one day standalone lesson plan, or it can be pieced together with other lesson plans from Slave Voyages to create a mini-unit on slavery and how to think like a historian. The basic framework of this activity can be scaled up for use in a high school classroom. For classrooms lacking in technology, the teacher can go to and print out the tables and charts, however the timelapse requires a computer to view.


NCHS Standar Four: Historical Research Capabilities

  1. Obtain historical data from a variety of sources, including: library and museum collections, historic sites, historical photos, journals, diaries, eyewitness accounts, newspapers, and the like; documentary films, oral testimony from living witnesses, censuses, tax records, city directories, statistical compilations, and economic indicators.
  2. Employ quantitative analysis in order to explore such topics as changes in family size and composition, migration patterns, wealth distribution, and changes in the economy.


This activity can be assigned as an in-class activity or as homework. It may also be assigned as a hybrid activity where some parts may be done at home. However, since access to a computer and internet is required, it is recommended that the activity only be assigned as homework if all students have the ability to complete the assignment.

Having students work individually on this activity is recommended, but the breaks between parts are an excellent opportunity for sharing answers and conclusions. Including a discussion in groups at the end of the activity is also a good idea to help students process the information they have just received. This can be a heavy topic for students. Leading a discussion with thoughtful and respectful questions will help students understand the content presented to them while realizing slavery is a major part of American history. Some questions you could present to students:

  1. What are some of the pieces of information that stick out to you most?
  2. What might be some of the difficulties and hardships in completing the trip from Africa to the Caribbean, and then being forced back onto another ship?
  3. Did this activity prove or disprove that slavery was a “southern problem” in the United States? Why or why not?
  4. Why do you think it is important to learn about the slave trade even though it is a sad and difficult topic?