Complex sentence: In 1092 Genoa and Pisa, in collaboration with Alfonso VI of León and Castile attacked the Muslim Taifa of Valencia; they also unsuccessfully besieged Tortosa with support from troops of Sancho Ramírez, King of Aragon.
Split into simpler sentences: In 1092 Genoa and Pisa, in collaboration with Alfonso VI of León and Castile attacked the Muslim Taifa of Valencia. They also unsuccessfully besieged Tortosa with support from troops of Sancho Ramírez, King of Aragon.