Had he issued orders for the rapid assembly of the army the French would have taken alarm.

He therefore sent private messengers to a number of knights and gentlemen of Kent and Sussex to meet him with their retainers at Dover on the 31st of December.
Walter was one of those summoned, and although much surprised at the secrecy with which he was charged, and of such a call being made while the truce with France still existed, he repaired to Dover on the day named, accompanied by Ralph and by twenty men, who were all who remained capable of bearing arms on the estate.
He found the king himself with the Black Prince at Dover, where they had arrived that day.

Sir Walter Manny was in command of the force, which consisted in all of 300 men-at-arms and 600 archers.

A number of small boats had been collected, and at midday on the 1st of January the little expedition started, and arrived at Calais after nightfall.
In the chivalrous spirit of the times the king determined that Sir Walter Manny should continue in command of the enterprise; he and the Black Prince, disguised as simple knights, fighting under his banner.
In the meantime a considerable force had been collected at St.Omer, where a large number of knights and gentlemen obeyed the summons of Jeffrey de Charny.

On the night appointed they marched for Calais, in number five hundred lances and a corresponding number of footmen.