 Henry's brother-in-law, Solomon of Hungary, sent envoys to Henry seeking his assistance against his cousin Géza (who was Béla I's eldest son).Géza had defeated Solomon on 14 March 1074, forcing him to take refuge in the fortresses of Moson and Pressburg (now Mosonmagyaróvár in Hungary and Bratislava in Slovakia, respectively).Solomon promised to cede six castles to Henry and acknowledge his suzerainty in return for Henry's support to recover his country.