Complex sentence: Rather than killing his wife's husband at Newton-le-Willows, it was Sir William Bradshaw who was slain there on 16 August 1333 in a fight with members of the Radcliffe family.
Split into simpler sentences: Rather than killing his wife's husband on Newton-le-Willows, it was Sir William himself who was slain there. On 16 August 1333, Sir William was killed in Newton-le-Willows in a fight with members of the Radcliffe family.