Moycullen is where I'm from, and I'd always known about the raids on the local co-op, then I read The Black and Tans by D.M. Leeson where he argues that all of Ireland underwent the Stanford Prison Experiment with the Tans as the Prison wardens.
There was an interesting piece about it, p 48
"...on Monday, 19 October, a mixed force of soldiers and Auxiliaries raided the cooperative society store at Moycullen. The store's manager, Lawrence Tallon, and his four male employees were told to put up their hands, and then were taken outside to stand against the side of a corrugated-iron hut. Tallon described the Auxiliaries as 'several men who were not in any regular uniform, but were a mixed lot. Some had police caps and portions of police uniform, and some had not.' Their leader work khaki breeches, a blue guernsey and a knitted blue tam-o'-shanter, held a revolved in one hand, and a whip in the other. Speaking with an English accent, he questioned one of Tallon's assistants, Macdonagh. When Macdonagh said he knew nothing about [Patrick] Joyce's kidnapping, the Auxiliary leader hit him in the face with his revolver.
'On my honour,' cried Macdonagh, 'I know nothing of the man. I have heard of him, that is all.'
'Well,' said the Auxiliary officer, we will make you know something.'
The police pulled Macdonagh's trousers down and whipped him. Then they treated a second man, Tim Connor, in the same way. When the manager protested that his assistants were innocent, he was threatened with a bayonet and told to go back inside. As Tallon turned to go back to the store, and Auxiliary pointed a shotgun at him. Tallon got his left hand up before the gun went off, and was wounded in the left arm and the left side of the neck. He stumbled back inside, where he found his female employees kneeling in prayer, terrified. Shortly thereafter, the police outside began shooting at the store, and kept firing their shotguns and rifles until their magazines were empty. (38)"
38 : Manchester Guardian, 22 October 1920, 9; The Times, 22 October 1920, 12; Connacht Tribune, 23 October 1920, 5.
Information about reprisals are in a large bound volume preserved at the National Archives of the UK, the register of Crime for the Province of Connaught - for researching it further.
The report of the Labour Commission listed 43 cases in which co-operative creameries and other socities were destroyed or damaged by the security forces, including the raid in the Moycullen co-op in Galway's West Riding on 18 October 1920 (sic)
"...murder...district councillor John Geoghegan, at Moycullen on 20 February 1921." p 189
Family legend says that the co-op was raided twice and it would probably be useful to check the 1921 date to see if there's further information in the UK National Archives info, my grandfather was one of the founders of this, along with a Colonel Kilkelly (whose
son died in World War II) and others. After the raids the insurance company (who are still around and major players) refused to pay out on the grounds that it was an "act of war". This lead to my grandfather having to sign over the land to his wife and declaring bankrupacy which put paid to him possibly being involved in Irish politics, which appeared to be what he was planning, having been involved in the Poor Law Union, Old IRA (where he refused to rise because he didn't believe in pikes against guns); GAA and Conradh na Gaeilge, among other interests. The bankrupcy was still being paid off in several households around the village well into the 50s. It basically ensured that Moycullen remained a backwater until it started filling with commuters.
Grandad Padraig Thornton aka Padraig O'Droighneain died in 1969, before I was born, it's funny sometimes to find him in historic documents.