Parliament is the supreme legislature of the United Kingdom. It consists of the House of Commons and the House of Lords. National councils to advise the monarch date back before the Conquest, but the origin of the modern parliament is generally dated to 1265, when Edward I called together an assembly at Westminster. Over the next several centuries, there was a struggle between Parliament and the monarch for supremacy. It led to the Civil War between Charles I and supporters of parliamentary rights. After James II was deposed by the Glorious Revolution, the monarch was made permanently subordinate to Parliament. The relative power of the hereditary House of Lords has diminished relative to the House of Commons and is now largely a formality.
Parliament meets in the Houses of Parliament in Westminster.