Robert Bertie, 1st Earl of Lindsey KG, previously 14th Baron Willoughby de Eresby was an English peer, soldier and courtier.

Peregrine Bertie, 13th Baron Willoughby de Eresby was the son of Katherine Willoughby, 12th Baroness Willoughby de Eresby, and Richard Bertie. Bertie was Lady Willoughby de Eresby's second husband, the first being Charles Brandon, Duke of Suffolk. Peregrine Bertie's half-brothers, Henry and Charles Brandon, died as teenagers four years before his birth. His sister Susan married the Earl of Kent and then the nephew of Bess of Hardwick. Owing to religious politics, his parents had to move outside England and the boy was born at Wesel on the River Rhine.