Complex sentence: Leofric, was Earl of Mercia from about 1017, until his death in 1057, he was one of the most respected men in England serving four king's loyally, his power rivaled that of Godwin, Earl of Wessex.
Split into simpler sentences: Leofric, was Earl of Mercia from about 1017 until his death in 1057. He was one of the most respected men in England, serving four kings loyally; his power rivaled that of Godwin, Earl of Wessex.