Mary of Guise (French: Marie de Guise; 22 November 1515 – 11 June 1560), also called Mary of Lorraine, was Queen of Scotland from 1538 until 1542, as the second wife of King James V. She was a French noblewoman of the House of Guise, a cadet branch of the House of Lorraine and one of the most powerful families in France. As the mother of Mary, Queen of Scots, she was a key figure in the political and religious upheaval that marked mid-16th-century Scotland, ruling the kingdom as queen regent on behalf of her daughter from 1554 until her death in 1560.
The eldest of the twelve children born to Claude, Duke of Guise, and Antoinette of Bourbon, in 1534 Mary was married to Louis II d'Orléans, Duke of Longueville, the Grand Chamberlain of France. The marriage was arranged by King Francis I of France, but proved shortlived. The Duke of Longueville died in 1537, and the widower kings of England and Scotland, Henry VIII and James V, both sought the Duchess of Longueville's hand. After much persuasion from Francis I and James V, who wrote a personal letter pleading for her hand and counsel, Mary eventually relented and agreed to marry the King of Scots. Following the new queen's arrival in Scotland, James and Mary were married in person in June 1538 at St Andrews Cathedral. Mary was crowned queen at Holyrood Abbey on 22 February 1540, and the marriage produced three children in quick succession: James, Duke of Rothesay; Robert, Duke of Albany; and Mary. Both sons died in April 1541, just 14 hours apart, and when James V himself died in December 1542, his only surviving heir, Mary, became Queen of Scots at the age of six days old.