Complex sentence: In 1750, he was appointed Governor of Carlisle, and also represented the town in the British parliament as the Member of Parliament for Carlisle (1741--42 and 1746--61).
Split into simpler sentences: In 1750, he was promoted to the government of Carlisle, which he represented in the British parliament in 1741. He was the Member of Parliament for Carlisle (1741--42 and 1746--61).