same authors, the writ ne exeat regno had its beginning.
By these, and the like arbitrary methods, having amassed great treasures, and finding all things quiet at home, he raised a powerful army to invade his brother in Normandy; but upon what ground or pretext, the writers of that age are not very exact; whether it were from a principle frequent among unjust princes, That old oppressions are best justified by new; or, whether having a talent for sudden enterprises, and justly apprehending the resentment of duke Robert, he thought it the wiser course to prevent injuries, than to revenge them. In this expedition he took several cities and castles from his brother, and would have proceeded farther, if Robert had not desired and obtained the assistance of Philip king of France, who came with an army to his relief. King William, not thinking it safe or prudent to proceed farther against his enemy, supported by so great an ally, yet loth to lose the fruits of his time and valour, fell upon a known and old expedient, which no prince ever practised oftener, or with greater success, and that was, to buy off the French king with a sum of money. This had its effect; for that prince, not able to oppose such powerful arms, immediately withdrew himself and his forces, leaving the two brothers to concert the measures of a peace.
This was treated and agreed with great advantages on the side of king William; for he kept all the towns he had taken, obliged his brother to banish Edgar Atheling out of Normandy, and for a farther security brought over with him to England the duke himself to attend him in his expedition against Mal-
