The regiment was renamed for Princess Frederica in 1798 as the 14th (The Duchess of York's Own) Regiment of (Light) Dragoons and allowed to use the Prussian Eagle as its badge. The regiment was dispatched to Lisbon in December 1808 to join Sir Arthur Wellesley's Army which was engaged in the Peninsular War. The regiment fought at the Second Battle of Porto in May 1809 during which one of the French brigade commanders, General Maximilien Foy, was wounded in an action involving a squadron of the regiment.