Complex sentence: Thereafter, he took his place in the House of Lords, while, for a period at the same time, acting as mayor of Eastbourne and Chesterfield, as well as holding various cabinet posts both prior to and after his rise to the peerage.
Split into simpler sentences: Thereafter, he took his place in the House of Lords, while, for a period at the same time, acting as mayor of Eastbourne and Chesterfield. He held various cabinet posts both prior to and after his rise to the peerage.