Matthew Stewart (1516-1571) was the 4th Earl of Lennox, and leader of the Catholic nobility in Scotland. In 1544 he married Margaret Douglas (1515-1578), niece of King Henry VIII of England.

Lennox was instrumental in the marriage of his son, Lord Darnley, to Mary Queen of Scots. In 1570, Lennox became regent for his grandson, James VI, but the Queen's party declared war against him and he was killed the next year.