Which came first, India or Pakistan?

Both arrived in 1947. India became independent from British rule. Pakistan became independent at midnight, one day before India.

Side by side

India

India became independent on 15 August 1947 and a republic on 26 January 1950, when the constitution took effect — which is why the country has two national days. It remained a dominion with the British monarch as head of state for those two and a half years. India as a civilisation is thousands of years older; India as a state with its present borders is younger than the ballpoint pen.

Pakistan

Pakistan and India were created by the same act of parliament, but Mountbatten had to attend both ceremonies, so he took the Pakistani one in Karachi on 14 August and the Indian one in Delhi on the 15th. Pakistan is therefore one day older than India in the sense the question means. Independence in both cases took effect at the same instant: midnight between the two dates.