Yes, the British Isles had two periods of civil war. The series of wars known as the Wars of the Roses
between the houses of Lancaster and York between 1455 and 1487.
The other was the English Civil War
of 1642 to 1651. This was the war of the Cavaliers and Round Heads. This later ended with Charles the first loosing his head and the establishment of a Republic under Oliver Cromwell. This rapidly descended into a brutal oppressive puritanical dictatorship in which the UK lost much art and almost all of its early organs. As far as I know the only church organ to survive this period of destruction is the organ at St Mary's Rotherhithe on the Thames from where the Mayflower sailed with the pilgrims after the end of the civil war.
It was the lessons of this civil war after the establishment of the Restoration colonies under Charles the second that in my view had the greatest influence on the framing of the US constitution, especially the prohibition of State religion, religious freedom and division of powers. It also is from where the US got its fervent religiosity especially in the early years.
As far as early Norse parliaments, I think you are referring to the Tynwalds.
One of the most fascinating places I have ever visited is the Isle of Mann, or Manx
. An island right in the middle of the Irish Sea which is a self governing British protectorate. It still has a Tynwald.
The island's parliament, Tynwald
, is claimed to have been in continuous existence since 979 or earlier, purportedly making it the oldest continuously governing body in the world, though evidence supports a much later date.
Tynwald is a bicameral or tricameral
legislature, comprising the House of Keys
(directly elected by universal suffrage with a voting age of 16 years) and the Legislative Council
(consisting of indirectly elected and ex-officio members
). These two bodies also meet together in joint session as Tynwald Court.
The executive branch of government is the Council of Ministers
, which is composed of members of the House of Keys. It is headed by the Chief Minister
functions of the head of state are performed by a lieutenant governor
This is a actually a distinct entity from what developed in in England in the years following the Norman Conquest of 1066.
Interestingly my best friend from School became secretary of the House of Keys, for six years or so. He developed an unusual capacity to quickly master languages and among other things became an expert linguist. I went to medical School and he to law school, both associated with the University of London.
Anyhow because of his gift of languages, soon out of law school he was engaged to draw up a good deal of the EUs trading and contract law. Originally it was the European Common Market and transmuted into the EEC we know today. Anyhow because of this knowledge he was recruited to the powerful position in the Isle of Man, which is a well known tax haven to advise how to get round the regulations he had constructed! Subsequently he has become a judge and used to adjudicate complex financial cases especially those with international connections. Now retired he had had an interesting life. He is an official translator of legal documents, and interestingly that includes translating from American and English and vice versa. For instance the word compensation has a totally different legal meaning in American and English. It was during his time in the Isle of Mann that I visited the place, and he was able to show me close up the workings of the Tynwald and especially the House of Keys.
Surprisingly my friend has become an ardent leaver of the EU strongly favoring Brexit. In his younger years he was a great enthusiast and promoter for the EU.