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, author 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 is to make the slave trade come alive for young readers.

Cottman is a journalist and scuba diver. Recently, he spoke about his own journey in writing the book.

The book came out of his own desire to learn more about the Henrietta Marie. The British slave ship sank off the coast of Florida in 1700. Like many colonial slave ships, the Henrietta Marie took part in what is called the "Triangle Trade." Ships transported captives from West Africa to the Americas. They sold enslaved people and brought raw materials, such as sugar or tobacco, from the Americas to Great Britain. Finally, the ships carried supplies and manufactured goods to British outposts in Africa to sell for enslaved people. The Henrietta Marie had just completed a journey to Jamaica to deliver enslaved people when it was hit by a hurricane. 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. Marine archaeologists discovered the shackles in 1972.

In 1994, Cottman decided he wanted to retrace the Henrietta Marie's journey himself.

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 referred to as "cargo" or "beasts," and never as humans.

The research was emotionally difficult, but 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 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 understand why people participated in the slave trade.

Through careful research, Cottman discovered the name of the British ironmonger who forged the shackles discovered in the wreck. His name was Anthony Tournay. For Cottman, Tournay shows how the slave trade was made up of ordinary men and women.

Excavating the Henrietta Marie

More than 7,000 artifacts were found in the Henrietta Marie. Experts think it was the largest trove of objects from the early years of the African slave trade. Marine archaeologists found glass beads, which were used to barter for African people, and a cauldron used for cooking.

Scuba divers from two organizations excavated the wreck and placed a memorial plaque at the site. The groups were the National Association of Black Scuba Divers and the Maritime Heritage Society, which is mainly white. For Cottman, the partnership of these black and white divers was one of the most important aspects of the book.

Cottman hoped 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 important purposes to come together on. It takes "people interacting with people who don't look like them," he said. This is especially important in our society, which is increasingly made up of people of different colors and backgrounds, said Cottman.

Shackles From the Deep is part detective story and part underwater mystery, Cottman said. It is also part personal journey.

By retelling the story of a shipwreck and underwater exploration, the book presents the topic of the slave trade in an active way. It also sends a critical message. 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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