The name has also been used as a given name since the 19th century.
The Sidney family rose to prominence in the Tudor period with the courtier Sir William Sidney (d. 1554). His son Henry Sidney (1529–1586) became a prominent politician and courtier. By Mary Dudley, Lady Sidney (d. 1586) he was the father of Philip Sidney (1554–1586), poet and courtier under Elizabeth I, Mary Sidney (1561–1621), married Mary Herbert, Countess of Pembroke and Robert Sidney, 1st Earl of Leicester (d.1626). The latter was created Baron Sydney of Penhurst in 1603. Following Robert, the Earls of Leicester bore the surname Sidney:
The first creation of the title Baron Sydney was extinct with the death of the 7th Earl of Leicester in 1743.
In 1768, Dudley Cosby, Minister Plenipotentiary to Denmark between 1763 and 1765, was made Baron Sydney (second creation), of Stradbally in the Queen's County, in the Peerage of Ireland. This creation became extinct on Lord Sydney's death in 1774.