Sir William Kirkcaldy of Grange (c. 1520 –3 August 1573) was a Scottish politician and soldier who fought for the Scottish Reformation. He ended his career holding Edinburgh castle on behalf of Mary, Queen of Scots and was hanged at the conclusion of a long siege. Family William Kirkcaldy of Grange held lands at Hallyards Castle in Fife. William's father, James Kirkcaldy of Grange (died 1556), was lord high treasurer of Scotland from 1537 to 1543 and a determined opponent of Cardinal Beaton, for whose murder in 1546 William and James were partly responsible. William Kirkcaldy married Margaret Learmonth, a sister of Sir Patrick Learmonth of Dairsie and Provost of St Andrews, and George Learmonth of Balcomie. Kirkcaldy's heir was a nephew. A few days before Kirkcaldy's execution in August 1573, Ninian Cockburn reported that he had a child with a young woman. Kirkcaldy wrote a letter in code to the woman from his captivity, which was intercepted and decoded. Later, Mary, Queen of Scots, corresponded in cipher with the French diplomat Michel de Castelnau about this woman and her daughter. Mary arranged to give the daughter 40 crowns in 1582. War with England, service with France, and the Reformation William Kirkcaldy, with other courtiers, was a witness to the instrument made at Falkland Palace at the deathbed of James V of Scotland in 1542 which Cardinal Beaton used to attempt to claim the Regency of Scotland. However, he participated in the Cardinal's murder in May 1546, and when St Andrews Castle surrendered to the French in July the following year Kirkcaldy was sent as a prisoner to Normandy. He escaped in 1550. Kirkcaldy was employed in France as a secret agent by the advisers of Edward VI, being known in the ciphers as "Corax". Later he served in the French army, where he gained a lasting reputation for skill and bravery. Kirkcaldy was in London in December 1553, discussing border issues with the French ambassador, Antoine de Noailles. The sentence passed on Kirkcaldy for his part in Beaton's murder was removed in 1556. Returning to Scotland in 1557, he became prominent by killing Ralph Eure, the brother of the Governor of Berwick upon Tweed, in a duel. As a Protestant he was one of the leaders of the Lords of the Congregation in their struggle with the Regent of Scotland, Mary of Guise. Kirkcaldy fought the French troops in