A Sunken Slave Ship and the Search for Answers

A Sunken Slave Ship and the Search for Answers

In Michael Cottman's new book, Shackles From the Deep, the history of the slave trade comes to life through underwater exploration, detective work, and the author's personal journey.


3 - 12


Anthropology, Archaeology, Geography, Social Studies, U.S. History, World History

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In Shackles From the Deep, journalist and scuba diver Michael Cottman explores the history of the slave trade. The book focuses on the journey of a single ship: the Henrietta Marie. Cottman's goal was to humanize the slave trade for young readers and transform the way slavery is traditionally taught into an active approach centered on curiosity and discovery.

Recently, Cottman spoke about his journey in writing the book. He talked about the importance of developing a passion and the unusual partnership that made the discovery possible.

The book began with his own desire to learn more about the Henrietta Marie, a British slave ship that sank in the Florida Straits in 1700. Like many colonial slave ships, the Henrietta Marie took part in the "Triangle Trade." It transported captives from West Africa to the Americas, raw materials, such as sugar or tobacco, from the Americas to Great Britain and finally, supplies and manufactured goods to British outposts in Africa. The ship had just completed a journey to Jamaica to deliver enslaved people when it was hit by a hurricane on its return voyage. The entire crew was killed. Although there were no African captives on board, the shackles and chains that had held them sank with the ship to the ocean floor. Marine archaeologists discovered the shackles in 1972.

In 1994, Cottman decided he wanted to retrace the Henrietta Marie's journey himself. As a scuba diver, he was in the perfect position to do so.

International Business of Slavery

Cottman began piecing together the history of the Henrietta Marie by reading historical records. Soon he became "overwhelmed with the fact that Africans were characterized as 'cargo' or 'beasts,' and never as humans."

Although emotionally difficult, Cottman was driven by his passion to understand the history of his ancestors. He hoped to send a message to young people about the importance of developing a passion and finding something that makes you excited to wake up and get to work.

Cottman explained that his work was also driven by a need for closure. He desperately wanted to gain an understanding of what motivated people to carry out the slave trade.

Through careful research, Cottman discovered the name of the British ironmonger who forged the shackles discovered in the shipwreck, Anthony Tournay. Tournay shows how the slave trade was made up of ordinary men and women. Likely capable of compassion in other circumstances, they were participating in what Cottman called "the international business of slavery."

Excavating the Henrietta Marie

Excavating the wreck of the Henrietta Marie led to the recovery of more than 7,000 artifacts. Experts think it was the largest source of objects representing the early years of the African slave trade. Some of the recovered items include glass beads, which were used to barter for African people, and a cauldron used for cooking.

Members of the National Association of Black Scuba Divers and the predominantly white Maritime Heritage Society carried out the excavation of the wreck and placed an underwater memorial plaque at the site. The partnership of black and white divers is one of the most important aspects of the book.

Cottman expressed his hope that young people will read his book and appreciate "the power of different ethnic or racial groups to work together for a common purpose." In this case, the common purpose was the excavation of a shipwreck. Yet, Cottman reminded readers that there are "many other purposes to come together on." It takes "people interacting with people who don't look like them, which is especially important in our expanding multicultural society."

"Shackles From the Deep is part detective, part mystery, part underwater exploration and part personal journey," according to Cottman.

By engaging students in a story about a shipwreck and underwater exploration, the book presents the topic of the slave trade in an active way. It sends the critical message that history is an ongoing process that students can participate in, Cottman said.

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Anna Lukacs, National Geographic Society
National Geographic Society
Anna Lukacs, National Geographic Society
Last Updated

October 19, 2023

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