Bach, bahk, Johann Christian (1735-1782), a German composer, was the youngest son of the famous composer Johann Sebastian Bach. Johann Christian is best known for his chamber music, symphonies, and operas in the Italian style. He was born on Sept. 5, 1735, in Leipzig, and lived there and in Berlin until he moved to Italy in 1754. From 1762 until his death on Jan. 1, 1782, he worked in London but made frequent trips to the continent. In London, he became known as "John Christian Bach."