May 26th , 1063
After the collapse of the Roman Empire in Britain during 410, Wales became divided into several kingdoms. Attempts by the Anglo-Saxon tribes to invade these kingdoms failed due to the fierce resistance of its people and its mountainous terrain.
The eastern lands lost to English settlement became known in Welsh as Lloegyr, the lost lands, and eventually became the modern Welsh name for England. The Anglo-Saxons, in turn, labelled the Romano-British as Walha, meaning foreigner or stranger. The Welsh countinued to call themselves as Brythoniaid (Britons) until as late as the 12th century, though the first use of Cymru and y Cymry were recorded as early as 633 by Aneirin. In the Armes Prydain written in about 930, the use of Cymry and Cymro was used as often as 15 times.
Following the Norman conquest of England in 1066, the independence of Wales was gradually eroded. In 1282, Edward I of England defeated Llywelyn the Last, Waless last independent Prince, in battle. Edward constructed a series of great stone castles in order to keep the Welsh under control.