Upton started his military career under royal patronage, for the Queen urged the Duke of York to give him a vacant ensigncy in the Coldstream Guards without purchase as he could not afford it. He was on active service for much of this period, in the Netherlands (1794, 1799, 1809) and in the Peninsula. In 1811 when he was posted to Cadiz, it was described as ‘a plan for getting Arthur Upton out of the country’.
In 1818 he was returned to Parliament for Bury by his brother-in-law the 5th Earl of Bristol. No vote of his either way, still less any speech, is known in his first Parliament. Gronow recalled him as a fund of anecdote about the royal family, a strict disciplinarian, but absent-minded. He was best known as a cricketer, who played in the first Gentlemen v. Players match in 1806, and he also featured as a violinist at fashionable musical soirees.
