Mary of Guise, 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 th…Mary of Guise, 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.