It founded the colony of Liberia in West Africa as a place to resettle free people of color from the United States.

[1][2] Drawn by other opportunities, Ashmun returned to the United States, settling in Washington, DC, where he worked as the editor of an Episcopalian monthly.

Interested in the work of the American Colonization Society (ACS), he founded the newspaper The African Intelligencer and wrote about their mission.

As United States representative to Liberia as well as agent of the ACS, Ashmun served as governor of the colony for two periods of time, from 1822 to 1828, from ages 28 to 34.

During his tenure in Liberia, Ashmun increased agricultural production, annexed more lands from neighboring tribes, and exploited commercial opportunities in the interior.

Nearly a century after his death, a British history of Liberia called Ashmun "one of the most remarkable men who have ever given their lives in the service of Africa and the African.