Original: In that same year, the Alhambra Decree was issued, expelling all Jews from both Castile and Aragon, and Christopher Columbus was sent by the couple on his expedition (ostensibly bound for east Asia) which resulted in the European arrival in the America.
Simplified: In that same year, the Jews were expelled from both Castile and Aragon, and Christopher Columbus was sent by the couple on his expedition which would ultimately discover the New World.