Complex sentence: Howard E. Rollins Jr had just had an Oscar nomination for his role in the Ragtime, and was cast as the lead, but he is only one example of the apt and excellent casting of a great black ensemble; most of whom came from Broadway.
Split into simpler sentences: Howard E. Rollins Jr had just had an Oscar nomination for his role in the Ragtime, and was cast as the lead. He is only one example of the apt and excellent casting of a great black ensemble; most of whom came from Broadway.