Americo-Liberians are a Liberian ethnicity of African American descent. The sister ethnic group of Americo Liberians are the Sierra Leone Creole people who are of African American, West Indian, and liberated African descent. Americo Liberians trace their ancestry to free-born and formerly enslaved African-Americans (who called themselves Americo Liberians) who immigrated in the 1800s to become founders of Liberia and other colonies along the coast in places that would become Cote d'Ivoire and Sierra Leone. Later, these African Americans integrated 5,000 liberated Africans called Congos (descendents of freed slaves from the Congo Basins who never made it to the Americas) and 346 Barbadian immigrants into the hegemony. Like the Creoles of Freetown, Americos rarely intermarried with Natives. For 133 years after independence, the Republic of Liberia was a one-party state ruled by the Americo-Liberian dominated True Whig Party.