2 February 1972: The British Embassy in Dublin was burnt down on this day. Some 20,000 people had gathered outside it on Merrion Square to protest at the deaths of 13 Civil Rights marchers in Derry three days before. There had been sporadic attacks on the edifice the previous night that had destroyed the front door that was quickly boarded up.

As the crowds gathered outside a grim cortege made its way to the front consisting of 13 symbolic black coffins - each one for the 13 men who were shot dead on Bloody Sunday. Within at least one were a number of petrol bombs consisting of a small amount of petrol and sugar.

Three young men climbed on to the balcony of the embassy. One ran a Tricolour up the flagpole outside the embassy and the other smashed the bulletproof window with a hatchet.

When that was achieved, another man doused the upstairs room with petrol and set fire to it with a match borrowed from the crowd who cheered every move. This was the queue for others to throw petrol bombs at the embassy.

https://www.irishtimes.com/news/ireland/irish-news/the-day-of-rage-after-bloody-sunday-that-saw-the-british-embassy-burn-down-1.4791709

The building was completely gutted as Dublin Fire Brigade could not get through the throngs of people to tackle the inferno and it is probable they had not the inclination to do so anyway, confining themselves to dousing the adjacent buildings to stop the flames from igniting them in turn.

The dramatic events of that day probably marked the nadir in Anglo-Irish relations since the War of Independence over half a century earlier. While there were many ups and downs in the years ahead nothing would ever be so bad again as it was then.