Roll of Irish Brigade in Zossen confirms service number. A Waterford man who joined the Royal Irish Regt around 1902. Taken prisoner during the Royal Irish Regiment's retreat at Mons. On MI5 files with this service number James Carroll (7453) and Keogh notes him as "James O'Carroll of Waterford". Mahony has him as being in Royal Irish, and records that Carroll did not volunteer for Egypt, which is probably the reason that Keogh did not keep up with him.
1886 Jun 24. State records give two James Carroll born in Waterford in 1886. He could be either of them.
1901 census, he could be either of the two 14 year olds in Co. Waterford. However he cannot be the one living in Smith's Lane, Waterford City - the 1911 shows the James from 1901 living in the same house with the same parents in 1911, when our man is in India with the army. So by elimination, he is probably the boy above living at Boola, Templemichael, Waterford.
1902. He service number implies that he was in Royal Irish Regiment about August 1902 so should be in the regiment during the 1911 census. Keogh says he served in Boer War with Major John MacBrides Irish Brigade and hence had the nickname "Kruger". It is unlikely that Carroll served under McBride, although he could perhaps have served with the Royal Irish in South Africa, though I can find no record of this. I suspect it is whimsy on Keogh's part in trying to show a link to MacBride
1911 census. There is a James Carroll given in 1911 census in 1st Battalion The Royal Irish Regiment, at Agra, India. Single, age 24 (so born 1886/87) in Waterford. This would seem to be him, in which case 14 year old in 1901 census above
1914 Lands in France on 13 Aug 1914. Taken prisoner and follows the same itinery as the rest of the Irish Brigade. He keeps a low profile and is not mentioned in any reports during the war. He did not volunteer for putative service in Egypt
1914 Taken prisoner, and followed the rest of the Irish Brigade through Limburg, Zossen and Danzig
1915 Oct. He gives his addres as Smith Lane, Ballybritton, Waterford (this is probably Ballybricken which is part of Waterford City)
1915 Dec 1. Did not volunteer for Egypt
There is no likely marriage or death in Waterford under Irish state registers
Dead by 1960 on Keogh's notes.
Recruits to Irish Brigade