The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of the continental mainland. It comprises England, Scotland, Wales and Northern Ireland, with a population of over 69 million in 2025. The UK includes the island of Great Britain, the north-eastern part of the island of Ireland, and most of the smaller islands within the British Isles, covering 94,354 square miles (244,376 km2). It shares a land border with the Republic of Ireland and is surrounded by the Atlantic Ocean, the North Sea, the English Channel, the Celtic Sea and the Irish Sea, while maintaining sovereignty over the Crown Dependencies and the British Overseas Territories. The capital and largest city of England and the UK is London; Edinburgh, Cardiff and Belfast are the national capitals of Scotland, Wales and Northern Ireland, respectively.
The British Isles have been continuously inhabited since the Neolithic. In AD 43 the Roman conquest of Britain began. The Roman departure between 383 and 410 was followed by Anglo-Saxon settlement beginning around 450. In 1066 the Normans conquered England. During the Tudor period, arts, trade, commerce, and exploration flourished. Over the 17th century the role of the British monarchy was reduced, particularly as a result of the English Civil War. In 1707 the Kingdom of England and the Kingdom of Scotland united under the Treaty of Union to create the Kingdom of Great Britain. The Acts of Union 1800 incorporated the Kingdom of Ireland to create the United Kingdom of Great Britain and Ireland in 1801. Most of Ireland seceded from the UK in 1922 as the Irish Free State, and the Royal and Parliamentary Titles Act 1927 created the present United Kingdom.
The UK became the first industrialised country in the world during the 18th century and was the world's foremost power for the majority of the 19th and early 20th centuries, particularly during the Pax Britannica between 1815 and 1914. The British Empire was the leading economic power for most of the 19th century, a position supported by its agricultural prosperity, its role as a dominant trading nation, a massive industrial capacity, significant technological achievements, and the rise of 19th-century London as the world's principal financial centre. At its height in the 1920s, the empire encompassed around a quarter of the world's landmass and population, and was the largest in history. The UK's involvement in the First World War and Second World War would damage Britain's economic power, and a global wave of decolonisation led to the independence of most British colonies, many of which became members of the Commonwealth of Nations. (Full article...)
The London congestion charge is a fee charged on most motor vehicles operating within the Congestion Charge Zone (CCZ) in central London between 07:00 and 18:00 (Monday-Friday only). The charge, which was introduced on 17 February 2003, remains one of the largest congestion zones in the world despite the cancellation of the Western Extension which operated between February 2007 and January 2011. The charge aims to reduce congestion, and to raise investment funds for London's transport system.
The standard charge is £10 each day for each non-exempt vehicle that travels within the zone, with a penalty of between £60 and £187 levied for non-payment. Enforcement is primarily based on automatic number plate recognition. Transport for London is responsible for the charge which has been operated by IBM since 1 November 2009. (Full article...)
Cædwalla (659–689) was the King of Wessex from about 685 until 688, when he abdicated. His name is derived from the British Cadwallon. He was exiled as a youth, and during this time attacked the South Saxons, in what is now Sussex, killing their king, Æthelwealh, but he was unable to hold the territory and was driven out by Æthelwealh's ealdormen. In either 685 or 686 he became king of Wessex. He may have been involved in suppressing rival dynasties at this time, as an early source records that Wessex was ruled by underkings until Cædwalla. After his accession Cædwalla returned to Sussex and won the territory again, and also conquered the Isle of Wight, extinguishing the ruling dynasty there. He gained control of Surrey and the kingdom of Kent, and in 686 he installed his brother, Mul, as king of Kent. Mul was burned in a Kentish revolt a year later, and Cædwalla returned, possibly ruling Kent directly for a period. Cædwalla was wounded during the conquest of the Isle of Wight, and perhaps for this reason he abdicated in 688 to travel to Rome for baptism. He reached Rome in April of 689, and was baptised on the Saturday before Easter, dying ten days later on 20 April 689. He was succeeded by Ine. (Full article...)

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