Complex sentence: However, the Lancastrians suffered a a crushing defeat, and Wenlock died on the battlefield, allegedly killed by his own commander, the Duke of Somerset, who blamed Wenlock's indecisiveness for the defeat.
Split into simpler sentences: However, the Lancastrians suffered a a crushing defeat, and Wenlock died on the battlefield. He was allegedly killed by his own commander, the Duke of Somerset, who blamed Wenlock's indecisiveness for the defeat.