Complex sentence: Upon their marriage, the Earl of Angus granted Gilbert and Margaret the manors of Hambleton and Market Overton; however, when Gilbert died childless prior to 1307, the manors passed to Margaret.
Split into simpler sentences: Upon their marriage, the Earl of Angus granted Gilbert and Margaret the manors of Hambleton and Market Overton. When Gilbert died childless prior to 1307, the manors passed to Margaret.