Complex sentence: In 1085, Alfonso VI of León and Castile captured Toledo, starting a gradual Muslim decline until, with the fall of Córdoba in 1236, the Emirate of Granada was the only Muslim territory in what is now Spain.
Split into simpler sentences: In 1085, Alfonso VI captured Toledo, starting a gradual Muslim decline. With the fall of Córdoba in 1236, the Emirate of Granada was the only Muslim territory in what is now Spain.