Free Derry and Bloody Sunday, Ireland

Between 1969 and 1972, Free Derry was a self declared nationalist area.  It was in the Bogside and Creggan neighbourhood.  Residents built barricades in January 1969 to keep the Royal Ulster Constabulary (RUC) out.  They took them down but continued to carry clubs threatening the RUC. Violence reached a peak on Aug. 14, 1969 with the Battle of Bogside, a three day battle between residents and RUC. The British Army was deployed but made no attempt to enter.  The Irish Republican Army (IRA) began to re-arm and recruit.   From Free Derry they began a bombing campaign in the city centre.  IRA popularity grew.
Bloody Sunday occurred January 1972 when the British Army 1st Battalion, Parachute Regiment (1-Para)  shot and killed 13 unarmed men and boys. One further died months later  in hospital.
On the Bloody Sunday day there was a march planned to go to the Guildhall but re routed to Bogside,  estimated between 5000 and 15000 .  Some of the members began throwing rocks at police.  Water hoses and rubber bullets were used. There was a report of an IRA sniper.  Live rounds were issued to the Paratroopers.  The crowd broke up and one young man was running alongside a priest away from the disturbance when he was fatally shot in the back.  A cease fire order was given but the British Army apparently shot into the fleeing crowd killing 12 more and wounding 14.  Armored personnel carriers knocked down some.
There were two enquires, the first considered a whitewash and after the second British Prime Minister Cameron apologized to the families of the dead.
After further killings by the IRA support for them decreased.
Thousands of British troops moved against Free Derry July 1972 with armoured cars and bulldozers.
(This abbreviation of events comes from Wikipedia, discussions in Ireland and a visit to the Bogside. There is a serious ‘fog of war’ surround this history and partisan bias.)