A popular Hindu story claims that Delhi was the site of the fabled city of Indraprastha, which is featured in the epic Mahabharata, over 3000 years ago. However, historical evidence suggests that the area has been settled for around 2500 years. Since the 12th century, Delhi has seen the rise and fall of seven major powers. The Chauhans took control in the 12th century and made Delhi the most important Hindu city in northern India. When Qutab-ud-din Aibak took over the city in 1193, he began six and a half centuries of Muslim rule. The Delhi Sultanate lasted from 1206 to 1526. It was followed by the mighty Moghuls from 1526 to 1857. The basis of what is today Old Delhi, including the Red Fort and the Jama Masjid, was built during the reign of the Moghul emperor Shah Jahan that lasted from 1628 to 1658. In 1803, the British captured Delhi and installed a British administrator. Delhi was not the capital of India at the time, but it was an important commercial center and had a population of 150,000 by the start of the 20th century.

When the British decided to make Delhi the capital in 1911, they built New Delhi in a grandiose imperial style, secure in the belief that the sun would never set on the British Raj. Only 16 years after the city was inaugurated as the nation's capital, Delhi was torched during the trauma of the partition into Hindu India and Muslim Pakistan. In a matter of weeks Delhi was transformed from a Muslim-dominated city of less than a million inhabitants to a largely Hindu city of almost two million.

Today, very few city residents can lay claim to being real Delhi-wallahs, and most of the population of New Delhi comprises Hindu-Punjabi families originally from Lahore. Since Independence, Delhi has prospered as the capital of India. In the past decade its population has increased by 50%, largely due to rapid economic expansion and increased job opportunities. The downside of this boom is increased overcrowding, traffic congestion, housing shortages and pollution.