Complex sentence: In 1216, Bohemond was overthrown with the help of Leo and Raymond Roupen was made Prince of Antioch; however, this only lasted until 1219 when Bohemond conquered and re-gained control.
Split into simpler sentences: In 1216, Bohemond was overthrown with the help of Leo, and Raymond Roupen was made Prince of Antioch. However, this only lasted until 1219 when Bohemond conquered and re-gained control.