Henry I of Brabant was a notable medieval ruler who reigned as the Duke of Brabant from 1183 until his death in 1235. He was the son of Godfrey III of Leuven and Margaret of Louvain, and he played a significant role in the political landscape of the Low Countries during his time. His reign was marked by efforts to strengthen the duchy and expand its influence. Henry I was also known for his support of the Catholic Church and his involvement in various military campaigns. He participated in the Crusades and worked to secure alliances through marriage, which helped to enhance the power and prestige of the Brabantian duchy.