Mary of Guise (French: Marie de Guise; 22 November 1515 – 11 June 1560), also called Mary of Lorraine, 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. She was Queen of Scotland from 1538 until 1542, as the second wife of King James V. 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 regent on behalf of her daughter from 1554 until her death in 1560.