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 also of African American descent. Most of them trace their ancestry to free-born and formerly enslaved African-Americans 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 Americo Liberians integrated 5000 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.

"The love of liberty brought us here", was the motto of some 13,000 persons who crossed the Atlantic to create new settlements on the Grain Coast of West Africa between 1817 and 1867 with the aid of the American Colonization Society. These settlers founded one of two African American colonies in West Africa, one being the nation of Liberia, the other being Freetown, Sierra Leone with their own descendants being referred to as 'Creoles'. The early settlers practiced their Christian faith, sometimes in combination with traditional African religious beliefs. They spoke an African American Vernacular English, and few ventured into the interior or mingled with local African peoples. Americo-Liberian society, culture and political organization remain heavily influenced by that of the United States, particularly the country's Southeast. Today the Americo-Liberian population numbers about 150,000.

http://en.wikipedia.org/wiki/Americo-Liberians