26/01/2015 3:15 PM IST | Updated 15/07/2016 8:24 AM IST

7 Little Known Things About India's Republic Day

PRAKASH SINGH via Getty Images
Indian Prime Minister Narendra Modi (L) talks with US President Barack Obama (R) while watching the fly-past during India's Republic Day parade on Rajpath in New Delhi on January 26, 2015. Rain failed to dampen spirits at India's Republic Day parade January 26 as Barack Obama became the first US president to attend the spectacular military and cultural display in a mark of the nations' growing closeness. AFP PHOTO/ PRAKASH SINGH (Photo credit should read PRAKASH SINGH/AFP/Getty Images)

India celebrated its 66th Republic Day today, with President Barack Obama as the chief guest, a first for an American president. Rains failed to dampen the festive mood, as thousands lined up along Rajpath in the national capital to witness a show of military strength and cultural diversity.

Here are 7 things you might not have know about this day:

1. In the first Republic day parade, more than 100 aircraft participated. Among them were Liberators, Spitfires, Dakotas, Tempests and Harvards. In comparison, this year's display had just 33 planes and helicopters.

2. The Indian Air Force came into existence this day. Prior to that it was known as the Royal Indian Air Force. Dropping the prefix was symbolic of Indian independence.

3. The Constitution was adopted on this day in 1950, and it declared India as a republic, hence the name. The first copy was of the constitution was not printed, but handwritten and calligraphed in Hindi and English.

4. The venue was not always Rajpath. Between 1950 and 1954 the venues of the Republic Day parade were Irwin Stadium (now National Stadium), Kingsway, Red Fort and Ramlila grounds. Rajpath, earlier known as Kingsway, became the permanent venue from 1955.

5. It would seem unimaginable now, but Republic Day chief guests have included ministers from Pakistan on two occasions. In 1955, it was Malik Ghulam Muhammad, Pakistan's Governor General. And in 1965, days before the war between the two countries, Rana Abdul Hamid, Pakistan's food and agriculture minister, was the chief guest.

6. Before the war with China in 1962, Ye Jianying, Marshal of the Chinese People's Liberation Army, was the chief guest the Republic Day parade. He later became chairman of the standing committee in China's government.

7. The song ‘Abide with Me’ is played on every Republic Day, because it was Mahatma Gandhi's favourite.