Anglo-Saxon Chronicle. Jun 1101. Then at midsummer went the king (age 33) out to Pevensey [Map] with all his force against his brother (age 50), and there awaited him. But in the meantime came the Earl Robert (age 50) up at Portsmouth, Hampshire [Map] twelve nights before Lammas; and the king (age 33) with all his force came against him. But the chief men interceded between them, and settled the brothers on the condition, "that the king (age 33) should forego all that he held by main strength in Normandy against the earl (age 50); and that all then in England should have their lands again, who had lost it before through the earl (age 50), and Earl Eustace also all his patrimony in this land; and that the Earl Robert (age 50) every year should receive from England three thousand marks of silver; and particularly, that whichever of the brothers should survive the other, he should be heir of all England and also of Normandy, except the deceased left an heir by lawful wedlock." And this twelve men of the highest rank on either side then confirmed with an oath. And the earl (age 50) afterwards remained in this land till after Michaelmas; and his men did much harm wherever they went, the while that the earl continued in this land.

After 25 Jul 1101 King Henry I "Beauclerc" England (age 33) and Robert Curthose III Duke Normandy (age 50), brothers, both sons of King William "Conqueror" I of England, signed the Treaty of Alton at Alton, Hampshire by which Robert Curthose III Duke Normandy (age 50) agreed to renounce his claim to the English throne in exchange for a yearly stipend and other concessions.