Complex sentence: After he himself died on 1 July 1566, his widow remarried Thomas Howard, 4th Duke of Norfolk, but died on 4 September 1567, so that Dacre's five young orphaned children grew up in the Duke's household.
Split into simpler sentences: After he himself died on 1 July 1566, his widow remarried Thomas Howard, 4th Duke of Norfolk. She herself died in 1567, so that Dacre's orphaned children grew up in the Duke's household.