The Treaty of Lambeth was signed on 4 May 1212 by King John of England and several French counts, including Renaud I of Dammartin and Boulogne and Ferdinand of Flanders.
[1] By 1212 John had lost his Angevin possessions in France.
Renaud lands had also been seized by King Philip II of France.
Renaud brought other continental nobles, including Ferdinand, into a coalition against Philip.
In the treaty agreed on 4 May 1212, each prince promised not to make a separate peace with France.