Konrad von Jungingen (also Conrad) (ca. 1355 – 30 March 1407) was the 25th Grand Master of the Teutonic Knights, serving from 1393 to 1407. Born in Jungingen in southwestern Germany, Konrad was the elder brother of Ulrich von Jungingen, who was his successor as Grand Master of the Teutonic Knights.An invasion army under Konrad conquered the island of Gotland in 1398, destroyed parts of Visby, and drove the Victual Brothers out of Gotland and the Baltic Sea. The Monastic State of the Teutonic Knights in Prussia was at the peak of its power during Konrad's leadership. Konrad died in 1407 at Marienburg Castle and was buried there. He died a most unusual martyr's death. His doctor prescribed sexual intercourse as a cure for his gallstones, from which von Jungingen was suffering at the time. The chaste knight refused to comply, and suffered the consequences.