Concordat of Worms
Out of fear of the Staufers, Lothair III placed himself under the pope's overlordship. He ceded to the pope all Imperial rights under Henry V's Concordat of Worms. War then broke out in Germany between those who supported the Staufers, and those who were aligned to Lothair and the pope. Upon Lothair's death, the Staufer Conrad III was elected, while Lothair's heir, Henry the Proud, of the House of Welf, continued fighting the Staufers.