Ethelred the Pious
The Jarldom of Ongellsey (Anglesey) currently forms a part of the Kingdom of England, but it has enjoyed a long history of political autonomy and cultural distinctiveness.
Work in progress.
Ongellsey was known as Môn in the original Welsh language. In the Ninth Century it formed part of the Kingdom of Gwynedd.
Like the Isle of Man, Ongellsey was a perfect base for Vikings to raid the coasts of England, Ireland, Wales, and Cornwall. After the Viking conquest of England, Ongellsey remained an important center for Viking Raids in the Irish Sea. Over the course of the Tenth Century, the island attracted a great many Scandinavians. Some brought their families, while others intermarried with the native Welsh population.
Ongellsey's long association with Nordo-Celtic Ireland began in 894, when King Sigfrid Ivarsson of Østangeln lost a battle to an army from the Kingdom of Dyflin (Dublin). King Anarwad of Gwynedd was forced to switch his feudal allegience: formerly he had paid tribute and fealty to Østangeln, but now he owed it to Dublin.
In 902 the Viking rulers were driven out of Dublin. They appealed in vain for aid to both of the Anglo-Norse kingdoms. They consequently settled in Ongellsey. While they had not defended their Irish kingdom against local rebels, they were able to successfully resist control by Gwynned's king. The Dublin Vikings formed the new Kingdom of Ongellsey.
The kingdom kept closer ties with the other Irish Norse than with the larger kingdoms in England. Dublin changed hands again, falling first to a Jorvikish fleet in 920 and then to Erik Bloodaxe in 935. Ongellsey remained independent and continued to attract Norse settlers fleeing the chaos in Ireland.
Ongellsey's brief period as a kingdom ended in 946, when Bloodaxe's son Erik the Mariner conquered it. The Bloodaxe War of the 960s and 70s left the island as the only vassal state of Dublin. The island's Þing was forced to acknowledge Helmut I, a grandson of Bloodaxe, as its Jarl. The Saga of Erik the Mariner was composed during the 970s or 80s: it is considered a masterpiece of Ongelseyan poetry and remains the isle's national epic.
Sweyn Forkbeard of Denmark was crowned King of Dublin in 999, and Ongellsey came with it. Helmut remained in power, however. When the Danish Empire disintegrated in the mid-Eleventh Century. Ongellsey remained connected with Ireland. There continued to be an exchange of people and culture between Ireland and Ongellsey, which had acquired a distinct flavor combining Welsh, Irish, and Scandinavian elements.
During the late medieval period, Ongellsey and most of Ireland were absorbed into the English kingdom. But Ongellsey was considered a separate country, and for cultural purposes remains one to this day.