Hamilton and Emma married five years later, when Hamilton obtained leave of three months in Britain. As he held a public position he had to ask the King's permission. The ceremony was a quiet one in St Marylebone parish church, taking place on 6 September 1791, two days before the couple's return to Naples. Emma signed the register as Amy Lyons; the witnesses were Hamilton's cousin the Marquess of Abercorn and Louis Dutens, who had been chaplain at Turin. The following day Hamilton was sworn of the Privy Council in 1791.