Sir Francis Knollys (born c. 1514—died July 19, 1596) was an English statesman, loyal supporter of Queen Elizabeth I of England, and guardian of Mary, Queen of Scots, during her early imprisonment in England.
Knollys entered the service of Henry VIII before 1540, became a member of Parliament in 1542, and was knighted in 1547 while serving with the English army in Scotland. A strong and somewhat aggressive supporter of the reformed doctrines, he retired to Germany soon after Mary I became queen, returning to England to become a privy councillor, vice-chamberlain of the royal household, and a member of Parliament under Queen Elizabeth I.
After serving as governor of Plymouth, Knollys was sent in 1566 to Ireland and in 1568 was sent to Carlisle to take charge of Mary, Queen of Scots, who had just fled from Scotland; afterward he was in charge of the Queen during her confinement at Bolton Castle and then at Tutbury Castle. He discussed religious questions with his prisoner, although the extreme Protestant views which he put before her did not meet with Elizabeth’s approval, and he gave up the position of guardian just after his wife’s death in January 1569. Knollys served as treasurer of the royal household from 1572 until his death.
Sir Francis’ daughter Lettice (1550–1634) married Walter Devereux, 1st earl of Essex, and then Robert Dudley, earl of Leicester; she was the mother of Elizabeth’s favourite, the 2nd earl of Essex.