John Bull (born 1562 or 1563; died March 15, 1628) was an English composer, musician, and organ builder. He was famous for playing the harpsichord and organ. Most of his compositions were written for keyboard instruments. He became a Gentleman, and then organist, at the Chapel Royal. He was also known for getting into trouble for adultery. He went to Europe and may have worked as a spy. He died in Antwerp.