John Cartwright, who has died aged 90, was the last president of the short-lived Social Democratic party, after much of it had merged with the Liberals to form the Liberal Democrats. He was one of those rare politicians whose unassuming characteristics belied a sharply instinctive understanding of politics far exceeding that of many of the better-known figures who strode the national stage during his four decades in public life.
He was MP for Woolwich in south-east London for 18 years from October 1974, first (for Woolwich East) on behalf of the Labour party and subsequently as a member of the SDP, for which he won the seat twice, in 1983 and 1987 – securing the best result in the country for the new party in 1983, thus demonstrating his personal popularity and the respect he had deservedly won from his constituents.
