Multiculturalism in the UK has its roots in the early seventeenth century. The UK had the biggest Empire in the history of the world - the British Empire. In the nineteenth century, it covered roughly 25% of the world's land surface and ruled around one-fifth of the entire population of the world. In the age of colonialism, the culture of all the colonies, like India, Australia, New Zealand, Egypt, and many other countries collided together. From 1801-81, the United Kingdom saw many immigrants arrive on British shores due to a booming economy domestically. In this period, over 2,000,000 people from Ireland moved to Great Britain, and over 1,500,000 from Germany and other parts of Europe arrived as well.