Two independent images — the lowering of the Union Jack, and Jawaharlal Nehru hoisting the tricolour and addressing the crowd at the Red Fort facing the Jama Masjid — were put together to make a perfect nationalist collage.
Interestingly, this narrative is factually wrong. The Independence Day ceremony did not take place at Red Fort on 15 August 1947, the ceremony as planned by the Indian leaders was much more solemn. The main event was to be organised at the Princess Park near the India Gate. It was initially decided that the Union Jack would be lowered and the Prime Minister would hoist the tricolour. This was to be followed by a small parade. However, the programme was changed at the last moment.

Mountbatten has given a detailed account of what transpired. He noted:

‘At 6 p.m. the great event of the day was to take place – the salutation of the new Dominion flag. This programme had originally included a ceremonial lowering of the Union Jack but when I discussed this with Nehru he entirely agreed that this was a day they wanted everybody to be happy, and if the lowering of the Union Jack in any way offended British susceptibilities, he would certainly see that it did not take place’. (Mountbatten Papers, British Library, BL/IOR: L/PO/6/123).

It seems that the Union Jack was not at all an issue for anyone. Rather, the organisers were more concerned about the crowd. Pamela Mountbatten noted in her diary that the grandstands were buried under the sea of people and the only sign of the parade was a row of bright pagdis somewhere in the centre at the Princess Park. It became very difficult even for Nehru and Mountbatten to reach the dais for the ceremony. Finally, Nehru unfurled the national flag, which was followed by the singing of the national anthem and the 31-gun salute.
The next morning on 16 August, Nehru hoisted the tricolour again. This time, the venue was the historic Red Fort. Nehru then delivered his first Independence Day speech, in which he called himself the Pratham Sewak of India. *
* theprint.in