Johannes Steinwert von Soest (Johannes de Susato) (1448 – 2 May 1506) was a German composer, theorist and poet. Most biographical details about his life survive in Johannes' verse autobiography, which was printed in 1811 (although the manuscript no longer survives) and has been partially translated into modern English. He was born in Unna and brought up in the nearby town of Soest. As a boy, he sang at the church of St. Patrokli. At one point a juggler almost succeeded in kidnapping him for his beautiful voice, but the plan did not succeed. The boy eventually left Soest when John I, Duke of Cleves hired him as a singer.