Complex sentence: He began his first strip for the Pulitzer papers on February 16,1902 with a continuing character, "Musical Mose", an African-American musician who impersonated other ethnicities, only to suffer the consequences when discovered by his audience.
Split into simpler sentences: He began his first strip with a continuing character, "Musical Mose", for the Pulitzer papers on February 16,1902. It starred an African-American musician who impersonated other ethnicities, only to suffer the consequences when discovered by his audience.