Sidney Sussex College is a constituent college of the University of Cambridge in England. The College was founded in 1596 under the terms of the will of Frances Sidney, Countess of Sussex (1531–1589), wife of Thomas Radclyffe, 3rd Earl of Sussex, and named after its foundress. In her will, Lady Sidney left the sum of £5,000 together with some plate to found a new College at Cambridge University "to be called the Lady Frances Sidney Sussex College". Her executors Sir John Harington and Henry Grey, 6th Earl of Kent, supervised by Archbishop John Whitgift, founded the Protestant College seven years after her death.

The University of Cambridge is a public collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the world's third-oldest university in continuous operation. The university's founding followed the arrival of scholars who left the University of Oxford for Cambridge after a dispute with local townspeople. The two ancient English universities, although sometimes described as rivals, share many common features and are often jointly referred to as Oxbridge.