Johann Michael Bach (baptised 19 August [O.S. 9 August] 1648 , Arnstadt, Schwarzburg-Sondershausen – 27 May [O.S. 17 May] 1694, Gehren) was a German composer of the Baroque period. He was the brother of Johann Christoph Bach, as well as second-uncle and father-in-law of Johann Sebastian Bach (he was the father of J.S. Bach's first wife Maria Barbara Bach). He is sometimes referred to as the "Gehrener Bach" to distinguish him from the "Wuppertaler Bach", Johann Michael Bach (1745–1820). Source : Wikipedia