Originally Posted by Anton Bruckner

He wrote all his clarinet works after his retirement, the clarinetist Mühlfeld inspired him so much by his beautiful playing that Brahms got out from being at ease and wrote a clarinet trio in a minor, 2 clarinet sonatas and the clarinet quintet. These clarinet works are beautiful.

Max Bruch a contemporary of Brahms wrote 8 pieces for Clarinet, Viola and Cello that I highly recommend along with the clarinet pieces by Brahms. Mozart also wrote some clarinet works that are the standard and the beginning of all subsequent clarinet works. Mozart is also highly recommend to see the beginning and the initial serious writing for the clarinet.