Home to the Indus Valley Civilization and a region of historic trade routes and vast empires, the Indian subcontinent was identified with its commercial and cultural wealth for much of its long history. Four major world religions, Hinduism, Buddhism, Jainism and Sikhism originated there, while Zoroastrianism, Judaism, Christianity and Islam arrived in the first millennium CE and shaped the region's diverse culture. Gradually annexed by the British East India Company from the early eighteenth century and colonised by the United Kingdom from the mid-nineteenth century, India became an independent nation in 1947 after a struggle for independence that was marked by widespread nonviolent resistance. India is a republic consisting of 28 states and seven union territories with a parliamentary system of democracy. It has the world's twelfth largest economy at market exchange rates and the fourth largest in purchasing power. Economic reforms since 1991 have transformed it into one of the fastest growing economies; however, it still suffers from high levels of poverty, illiteracy, and malnutrition. A pluralistic, multilingual, and multiethnic society, India is also home to a diversity of wildlife in a variety of protected habitats.