Simplify the following text for a Grade 13 native English-speaking person.
Original: On January 2 , 1492 , the last Muslim leader , Muhammad XII , known as Boabdil to the Spanish , surrendered complete control of Granada , to Ferdinand and Isabella , Los Reyes CatÃ licos ( `` The Catholic Monarchs '' ) , after the city was besieged .
Simplified: On January 2 , 1492 , the last Muslim leader , Muhammad XII , surrendered complete control of Granada , to Ferdinand and Isabella , after the city was besieged .