The Treaty of Lambeth of 1217, also known as the Treaty of Kingston to distinguish it from the Treaty of Lambeth of 1212, was a peace treaty signed by Prince Louis of France in September 1217 ending the campaign known as the First Barons" War to uphold the claim by Louis to the throne of England. When the campaign had begun, baronial enemies of the unpopular John, King of England had flocked to the French banner, but after John"s death in 1216, and his replacement by a regent, William Marshall, on behalf of the boy king Henry III, many had moved to the English side. Subsequent defeats at Lincoln in May 1217, at Dover and Sandwich in August 1217 forced Louis to negotiate.
