Elizabeth II
Amid preparations for the coronation, Princess Margaret informed her sister that she wished to marry Peter Townsend, a divorce' 16 years Margaret's senior, with two sons from his previous marriage. The Queen asked them to wait for a year; in the words of Martin Charteris, "the Queen was naturally sympathetic towards the Princess, but I think she thoughtshe hopedgiven time, the affair would peter out." Senior politicians were against the match and the Church of England did not permit remarriage after divorce. If Margaret had contracted a civil marriage, she would have been expected to renounce her right of succession. Eventually, she decided to abandon her plans with Townsend. In 1960, she married Antony Armstrong-Jones, who was created Earl of Snowdon the following year. They divorced in 1978; she did not remarry.

Q: Who did Princess Margaret marry in 1960?
Antony Armstrong-Jones