John of Brienne was a notable medieval figure born around 1170. He served as the King of Jerusalem from 1210 to 1225 and was a member of the noble family of Brienne. His reign was marked by efforts to strengthen the Christian presence in the Holy Land during the Crusades. In addition to his kingship, John was also a skilled military leader. He played a significant role in various battles against Muslim forces and was known for his diplomatic efforts, including his marriage to Maria of Montferrat, which helped to solidify alliances in the region.