In the late 18th century, many African-Americans claimed the protection of the British Crown. There were thousands of these Black Loyalists, people of African descent who joined the British military forces during the American Revolutionary War. Many of these Loyalists had been slaves who escaped to join the British, lured by promises of freedom (emancipation). The official documentation known as the Book of Negroes lists thousands of freed slaves whom the British evacuated from the nascent United States and resettled in colonies elsewhere in British North America (north to Canada, or south to the West Indies).