In the early Middle Ages Hesse had been part of the landgraviate of Thuringia, but following the War of Thuringian Succession it was inherited by the younger son of Henry II, Duke of Brabant. Henry I, Landgrave of Hesse also calles Henry the Child became the first Landgrave of Hesse in 1246. Between 1458 and 1500 the landgraviate was divided in Upper Hesse and Lower Hesse. The Landgraviate rose to primary importance under Philip I, Landgrave of Hesse also called Philip the Magnanimous who embraced Protestantism in 1524 and thereafter took steps to create a protective alliance of protestant princes and powers. Upon the death of Philip I in 1567, the Landgraviate was divided between his sons from his first marriage into the: