People celebrate the Chinese Dragon Boat Festival in honor of the poet Qu Yuan, who drowned himself after his country was invaded. People race boats to try to rescue him, and beat drums to scare away the fish that might try to eat him.

Personally, I don't think it's a boring sentence! :-) BUT If the person you are speaking to already knows you are talking about the festival then perhaps you can reduce the sentence by not repeating the words "Chinese festival" and just use 'it' : "It commemorates the heroic poet, Wan Yuen, who protested against corruption by drowning himself."