[W.S.J.] ] But an incident soon offered, which gave King Henry a pretext for retaliating almost in the same manner: for it happened that upon some offence taken against his nephew Theobald Count of Blois by the French King, Louis in great rage sent an army to invade and ravage the earl's territories.

Theobald defended himself for a while with much valour; but at length in danger to be overpowered, requested aid of his uncle the King of England, who supported him so effectually with men and money, that he was able not only to defend his own country, but very much to infest and annoy his enemy.

Thus a war was kindled between the two kings; Louis now openly asserted the title of William the son of Robert, and entering into an alliance with the Earls of Flanders and Anjou, began to concert measures for driving King Henry out of Normandy.
The King having timely intelligence of his enemy's designs, began with great vigour and dispatch to prepare himself for war: he raised, with much difficulty and discontent of his people, the greatest tax that had ever been known in England; and passing over into Normandy with a mighty army, joined his nephew Theobald.

The King of France, who had entertained hopes that he should overrun the duchy before his enemy could arrive, advanced with great security towards the frontiers of Normandy; but observing an enemy of equal number and force already prepared to engage him, he suddenly stopped his march.

The two armies faced one another for some hours, neither side offering battle; the rest of the day was spent in light skirmishes begun by the French, and repeated for some days following with various success; but the remainder of the year passed without any considerable action.
1119.
At length the violence of the two princes brought it to a battle: for Louis, to give a reputation to his arms, advanced towards the frontiers of Normandy, and after a short siege took Gue Nicaise;[23] there the King met him, and the fight began, which continued with great obstinacy on both sides for nine hours.