The Moa Flat farmer hardly ever spoke about the five years he served overseas with the Otago Infantry in World War 1, and a house fire was believed to have claimed his medals, war souvenirs, photographs and other memorabilia.
Mr O’Connor died in 1960, aged 73, and his descendants had few tangible objects to remember him by.
With advancing technology making collection and collation of soldier’s details, records and photographs easier, his granddaughter Erin McNaught took to facebook last year and contacted Southlander Iain Davidson, whose page "Unknown Warriors of the NZEF''attempts to put names to sepia-tinted images of old diggers.
Ms McNaught hoped that Mr Davidson might have in his possession, or know the whereabouts of, a photo of her grandfather taken while he was in the army.
On that front Mr Davidson could not help but he did have a much greater treasure for Ms McNaught and her three brothers — a diary kept by their grandfather during the final days of World War 1.
No-one in the family knew the diary existed.
Mr Davidson found the diary in an Invercargill secondhand store and painstakingly transcribed it — a task which took many days, due to Mr O’Connor’s small, cramped handwriting.
He has now sold it to Mr O’Connor’s descendants for the price he paid for it.
By the time Sergeant O’Connor first set pen to paper, in September 1918, he had been in service the entire war.
J. J. O’Connor left the family farm to enlist as a private in 1914.
After training in Egypt (where he served 14 days confined to barracks for "causing a disturbance") he had his baptism of fire on the afternoon of April 25, 1915, when he and the Otagos landed at Gallipoli.
Pte O’Connor remained on the peninsula until he and his comrades were evacuated later that year, and was a rare example of a first-day soldier who survived the duration without succumbing to battlefield injury or illness.
After that experience farm boy Pte O’Connor was no doubt relieved to be transferred to the transport section, where he had responsibility for the horse teams and wagons which ferried men, munitions and supplies to the front line.
While no longer actively fighting, Pte O’Connor would have seen bloodbaths such as the Somme, Messines and Passchendaele at close quarters.
Not that being behind the lines guaranteed safety: his diary records shells falling across the road from his quarters, his being caught in poison gas attacks, and falling into shell holes.
The diary Mr Davidson bought starts on September 6, 1918, as New Zealand troops were about to attack Trescault Spur, in northern France.
An at times irreverent account — his scorn for some of his superior officers is patent — it is also serious and compassionate, as the recently promoted Sgt O’Connor was highly concerned for the wellbeing of the recently liberated French civilians he encountered.
Perhaps Sgt O’Connor started a diary because he sensed the fighting was almost over — the October 6 entry said "the Huns are retreating all along the line and we all seem to think the war will be over by the end of the year."
A day later he availed himself of a privilege available to the transport section: "They have been putting in a lot of gas over but lucky to escape. Went for a long ride on Tiny to the canal and you would never think there was a war on. Tiny is some good in the trenches, she is just like a goat, goes in places where a man would not go."
The following week Sgt O’Connor contracted "a beautiful dose" of influenza, but recovered in time to move on with the brigade — and was twice caught in shelling as a result.
"My luck must have been right in, all the others seemed to be gassed."
Shortly afterwards Sgt O’Connor embarked on leave, and he was in Glasgow for Armistice Day, getting "very drunk" with a friend called Bob, cavorting with "a nice little Scotch lass" and getting into various scrapes.
"They locked the door of a good hotel and we could not get in so I pushed in a pane of glass," he wrote on November 13.
"There was a hell of a row, the police came up and made great enquiries and looked at my boots and found glass in them.
"Their hunch was too strong and I had to admit I done it. Don’t know how I will get on."
Not too badly, it turned out, as Sgt O’Connor received the Meritorious Service Medal in January 1919, for never failing to get forward and keep the battalion supplied throughout the offensive.
Like many Otago soldiers at war’s end, Sgt O’Connor remained marooned in England awaiting transport home, taking leave in Scotland — where he "learnt a lesson" after being "taken down for eight pounds" — and Ireland.
Thanks to his long service Sgt O’Connor secured a berth on the Athenic, just the sixth of 96 ships which brought New Zealand service personnel home again.
After a 45-day voyage, via the Panama Canal, on March 19, 1919 Sgt O’Connor "arrived at last in our beautiful land, New Zealand.
"I got a great surprise when we came in near Wellington. I always thought it was a big place from the boat. It looked like a bush town."
A day later he caught the Lyttelton ferry, then a train to Dunedin, before leaving the city for home on the Sunday.
After four years and 231 days total service, all but 74 days of it overseas, Mr O’Connor was home.
"Arrived home at 6am and I could not believe my eyes to see how everything has grown and looking so well," he wrote.
"It seems like one long dark dream that I have been through and I have been away for 20 years, the changes that have taken place."
James O’Connor married Maud in 1926 and they had two sons, but they had only 13 years together before her death in 1939.
Although he did not speak of his war experiences, there were clues that they continued to haunt Mr O’Connor: he could not bring himself to euthanise any of the farm’s animals and had to call upon neighbours to help.
Ms McNaught’s sole photo of her grandfather shows him smiling and flanked by his farm dogs.
If Mr Davidson had not found a dusty diary no-one knew existed, that image might have been all there was to say about James Joseph O’Connor, but now his family have so much more to tell.
