Inspired by the success of the Haitian Revolution, the origins of black and indigenous African nationalism in political thought lie in the 19th and early 20th centuries with people such as Marcus Garvey, Benjamin "Pap" Singleton, Henry McNeal Turner, Martin Delany, Henry Highland Garnet, Edward Wilmot Blyden, Paul Cuffe, and others. The repatriation of African-American slaves to Liberia or Sierra Leone was a common black nationalist theme in the 19th century. Marcus Garvey's Universal Negro Improvement Association of the 1910s and 1920s was the most powerful black nationalist movement to date, claiming millions of members. Garvey's movement was opposed by mainline black leaders, and crushed by government action. However, its many alumni remembered its inspiring rhetoric.