A musical genius but a dreadful person with strong anti-Semitic views he was one of the most influential composers romantic period?

The composer you are referring to is Richard Wagner. He was a German composer, theatre director, polemicist, and conductor who is primarily known for his operas. Despite his immense talent and influence in the world of music, Wagner held strong anti-Semitic views and made several derogatory remarks about Jewish people throughout his life. His writings on Jewishness, particularly his essay "Judaism in Music", have been widely condemned for their hateful and anti-Semitic content. Wagner's anti-Semitism has often overshadowed his musical achievements and has been a subject of much debate and controversy.