The following is a timeline of the history of Delhi, including New Delhi. Changes in ruling nation are in bold, with a flag to represent the country.
continuously inhabited since the 6th century BC,
731/736 – Lal Kot founded by the Tomar dynasty,
c. 1160 – Chauhan rulers take Lal Kot from the Tomars,
1180 – Lal Kot renamed to Rai Pithora,
1192 – Second Battle of Tarain, Delhi sacked by Muhammad Ghori and put under Muslim rule.
1206 – Delhi Sultanate: Qutb-ud-din Aibak becomes first Sultan of Delhi. Delhi is the capital.
1303 – Siri Fort built in Delhi.
1398 – Timur Lenk sacks Delhi.
1526 – Mughal Empire: The First Battle of Panipat creates the Mughal Empire, centered at Agra and Delhi.
1556 – Second Battle of Panipat, and Mughals retake Delhi from Suri dynasty.
1639 – Shahjahanbad (Old Delhi) is founded by Mughal emperor Shah Jahan.
1737 – First Battle of Delhi, where Mughal Delhi is sacked by Marathas.
1739 – Nader Shah of Persia conducts the Sack of Delhi.
1757 – Ahmad Shah Durrani sacks Delhi.
1771 – Delhi becomes a Maratha protectorate, under Mahadji Shinde.
1803 – Company Rule: Battle of Delhi between the Marathas and British East Indian Company.
1804 – Siege of Delhi by Marathas.
1857 – Indian Rebellion of 1857 begins in several cities, including Delhi.
1858 – British Raj
1911 – Delhi is once again the capital of the British Raj.
1927 – New Delhi founded.
1931 – New governmental quarter of Delhi inaugurated by architect Edwin Lutyens. It is called Lutyens' Delhi.
1947 – Dominion of India: New Delhi becomes the capital of India.
1950 – India
1956 – Delhi is made into a Union Territory.
1991 – Delhi is formally made into a National Capital Territory.
2001
2001 Indian Parliament attack takes place.
Population: 13,782,976
2002 – Delhi Metro begins operation.
2011 – Population: 16,753,235
Timeline of Delhi Wikipedia (Text) CC BY-SA