Book excerpt: The United Kingdom is a sovereign country located off the northwestern coast of continental Europe. It is made up of four countries - England, Scotland, Wales, and Northern Ireland. With a population of over 66 million, the United Kingdom is the 22nd most populous country in the world. London, the capital city, is the largest city in the UK and one of the most important financial centers in the world. The United Kingdom has a long and fascinating history. It has been inhabited by various groups of people over the centuries, including the Celts, Romans, Anglo-Saxons, and Normans. It has also played a significant role in world history, particularly during the colonial era when the British Empire was one of the most powerful forces in the world. Today, the United Kingdom is a modern, diverse, and multicultural society with a thriving economy and a rich cultural heritage. It is a member of the European Union, the United Nations, the Commonwealth of Nations, and NATO.