Horace Roscoe Cayton Sr. (1859–1940) was an American journalist and political activist. The son of a slave and a white plantation owner's daughter, Cayton went to Seattle, Washington, in the early 1890s, launching his own newspaper, the Seattle Republican, in 1894. The paper was the longest-lived of seven African-American newspapers appearing in Seattle between 1891 and 1901, terminating only in 1913.