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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Shackles From the Deep is a book about the slave trade. It tells the story of a single ship, the Henrietta Marie. The book's author, Michael Cottman, wanted 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.

Cottman wanted to learn more about the Henrietta Marie. The British slave ship sank off the coast of Florida in 1700. Like many slave ships, the Henrietta Marie took part in what is called the "Triangle Trade." Ships transported captives from West Africa to the Americas. Merchants sold the enlaved people and brought raw materials, such as sugar or tobacco, from the Americas to Great Britain. Finally, ships carried supplies and goods to Africa to buy more enslaved people. The Henrietta Marie had just delivered enslaved people to Jamaica when it was hit by a hurricane. The entire crew was killed. There were no enslaved people on board. However, the shackles and chains that held them sank with the ship. Marine archaeologists discovered the shackles in 1972.

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

International Business of Slavery

Cottman began learning the history of the Henrietta Marie by reading historical records. In them, Africans were called "cargo" or "beasts," and never humans.

Cottman was very upset to read that. However, he kept going, because he wanted to understand the history of his ancestors. He also hoped to send a message to young people about passion. It's important to find something that makes you excited to wake up and get to work, he said.

Cottman explained that he was driven by another reason, as well. He desperately wanted to understand why people participated in the slave trade.

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

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 slave trade. Among them were glass beads, which were used to barter for African people. Divers also found a large iron pot for cooking.

Scuba divers from two groups excavated the wreck and placed a marker there. The groups were the National Association of Black Scuba Divers and the Maritime Heritage Society, which is mainly white. For Cottman, their partnership was one of the most important parts of the book.

Cottman hopes that young people will see how the two groups worked together for a common purpose. There is a lot of power in that. Still, Cottman reminded readers that there are many other important causes. We need to work together with people who look different, Cottman said. This is especially important now, he said. More and more, the U.S. is made up of people of different colors and backgrounds.

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

The book also sends a critical message. History is not made up of just events in the past. It is an ongoing process that students can take part 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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