Henry Wriothesley, 2nd earl of Southampton (baptized April 24, 1545—died October 4, 1581, Itchel Manor, near Farnham, Hampshire, England) was one of the Roman Catholic English nobles who conspired for the release of Mary, Queen of Scots.
Henry Wriothesley was the third and only surviving son of the 1st Earl of Southampton and was born into great privilege (King Henry VIII himself was one of the sponsors at his baptism). During the reign of the Protestant Elizabeth I, however, he gained a reputation as a zealous Roman Catholic. In June 1570, at age 25, he was arrested for alleged complicity in the proposed marriage of Thomas Howard, 4th Duke of Norfolk, to Mary, Queen of Scots, and was imprisoned from July to November 1570 and from October 1571 to May 1573—during the latter period, in the Tower of London. Thereafter, he held a minor post in the county of Southampton and apparently withdrew from politicking.