Afican Americans first appeared in film around the turn of the 20th century. As you can imagine much if not most of these productions were stereotypical and racist.

I have read that vaudevillian Bert Williams was the first African American cast in a starring role. The short film called was DarkTown Jubilee (1914).

He was born in Antigua in 1874 or 1875. The family came to the US around 1885 and settled in NY. They moved to California where he completed his education and
began performing in a minstrel show.

He and his partner George Walker played vaudeville and had a show on Broadway until 1908 or 1909 when George became ill and died in around 1910 or 1911.

Bert's solo career began with Ziegfield's follies and he signed a contract with Columbia Records to record 4 songs from the show.

The Biograph Company hired him in 1916 to write, direct and star in "Natural Born Gambler" and "Fish".
http://www.archive.org/details/natural_born_gambler
As he was in his act, Bert performed in black face as was required of him in this movie.

In December 1921 he performed in "Under the bamboo tree"

Bert Williams fell ill and died March 4, 1922.

There's much information that has been written on him and if you'd like to see or hear some of his work go to www.internetarchive.org and do a search for him.