"Hang British Murder Troops" said a banner held aloft outside the British embassy in Merrion Square as the building was set on fire.
Coffins and other placards fuelled the flames as anger boiled over in Dublin at the Bloody Sunday massacre in Derry three days before. The Government agreed to pay compensation for the burning of the embassy.
It was the biggest demonstration in the Republic in a generation: 71 people were injured in baton charges as thousands registered their outrage at the killing of civil rights marchers by British troops.
The fallout from the events of January 30th, 1972, was acutely felt in the Republic. The day after the civil rights protesters were killed, 200 gardai had baton-charged a crowd at the end of a Sinn Fein meeting in Dublin, preventing an attempt to torch the British embassy. As a flame illuminated the face of the building, petrol bombs were dropped at its base.
When gardai moved out on to the square, demonstrators threw stones and petrol-bombs and some tried to storm the building. Several people were injured.
Students and workers meanwhile united in a gesture of solidarity with the people of the Bogside.
Throughout the afternoon, thousands of men, women and children descended on the British embassy, in a show of strength which would be replicated over the coming days. Political prisoners at Mountjoy Prison in Dublin announced a hunger-trike.
The Union Jack was burned in Patrick Street, Cork, as nearly 10,000 people took to the streets, and the Ulster Bank had to be evacuated after a bomb scare.
The British flag was also set alight as trade unionists marched on the centre of Cork city. The demonstration had followed a decision by 400 dockers to stop work in protest at the killings in Derry.
The angry mood continued the following day. The Waterford Docks Office was blown up and bottles and petrol-bombs were thrown at the doors of the besieged embassy.
The British Rail office, Woolworth's store and the Royal Insurance Group offices in Cork were all evacuated following bomb warnings. Work and transport stoppages escalated, bringing many parts to a standstill.
February 2nd saw a national day of mourning in the Republic. The President, Mr de Valera, and the Taoiseach, Mr Lynch, were among those who attended a special Mass at the Pro-Cathedral, while almost 3,000 filled St Patrick's Cathedral to mark the sombre occasion.
Speaking at a Mass at Killarney Cathedral, the Bishop of Kerry, Dr Eamonn Casey, urged the setting up of a national Irish news agency which would tell the world of the horrors of the events in Derry.
He believed that world opinion could convince the British leaders of the error of their ways and force them to abandon a policy which would only lead to further carnage.
Violent scenes erupted again the following day. A straw-stuffed effigy of the British prime minister, Mr Edward Heath, was doused with petrol in the street directly opposite the British Rail office in Cork and, as it was set alight, petrol-bombs were thrown through the windows of the premises.
The disorder was not just confined to cities. British-owned houses in Oughterard, Connemara, were vandalised, after an explosion which damaged a retired British admiral's home in the village the previous night.
Twelve British competitors were meanwhile forced to withdraw from a Galway car rally after the Moycullen GAA club in Connemara objected to their taking part. Earlier, an amateur boxing tournament with England had to be postponed.