The Treaty of Mantes was affirmed between

Charles II of Navarre Charles II (10 October 1332 – 1 January 1387), called Charles the Bad, was King of Navarre 1349–1387 and Count of Évreux 1343–1387. Besides the Pyrenean Kingdom of Navarre, Charles had extensive lands in Normandy, inherited from his fathe ...

and

John II of France John II (french: Jean II; 26 April 1319 – 8 April 1364), called John the Good (French: ''Jean le Bon''), was King of France from 1350 until his death in 1364. When he came to power, France faced several disasters: the Black Death, which killed ...

on 22 February 1354. After Charles began negotiating with

Edward the Black Prince Edward of Woodstock, known to history as the Black Prince (15 June 1330 – 8 June 1376), was the eldest son of King Edward III of England, and the heir apparent to the English throne. He died before his father and so his son, Richard II, suc ...

and

Henry of Grosmont Henry of Grosmont, Duke of Lancaster (– 23 March 1361) was an English statesman, diplomat, soldier, and Christian writer. The owner of Bolingbroke Castle in Lincolnshire, Grosmont was a member of the House of Plantagenet, which was ruling ov ...

, John II, in order to secure his alliance against England, sent Robert le Coq to

Mantes Mantes-la-Jolie (, often informally called Mantes) is a commune in the Yvelines department in the Île-de-France region of north-central France. It is located to the west of Paris, from the centre of the capital. Mantes-la-Jolie is a subpre ...

to negotiate his own peace treaty with the king of Navarre. By the treaty, Charles was created Count of Beaumont-le-Roger and John made many concessions, but the peace he desired was not sustained. Charles concluded an alliance with Henry of Grosmont later that year. This forced new negotiations, which led to the Treaty of Valognes, the next year.

Sources

*Funk, Arthur Layton
"Robert Le Coq and Etienne Marcel."
''Speculum'', Vol. 19, No. 4 (Oct., 1944), pp 470–487. *Zacour, Norman P.
Talleyrand: The Cardinal of Périgord (1301-1364).
''Transactions of the American Philosophical Society'', New Ser., Vol. 50, No. 7. (1960), pp 1–83.

1350s in France

1354 in Europe {{europe-hist-stub