Complex sentence: His acting career was interrupted by the Second World War (during which he served in North Africa and Anzio) but he returned to rep after the war, whilst also working as a publican and a labourer.
Split into simpler sentences: His acting career was interrupted by the Second World War (during which he served in North Africa and Anzio). He returned to rep after the war, whilst also working as a publican and a labourer.