- Born 23 April 1846 Ballinasloe, Co Galway
- Died 19 January 1918 1 De Vesci Terrace, Kingstown (Dun Laoghaire) Co Dublin
- Educated Mr Guillimand's School Dublin University
- Occupation Ennis College; Dublin University
- Debut 17 June 1869 v All England XI at Rathmines
- Cap Number 24
- Style Right hand bat
- Teams Ballinasloe, Galway CC, Co Galway
Jack Kempster was a member of a well-known Co Galway family, his father being the county surveyor. The Kempsters were also fine cricketers, Jack's younger brother, Frank, scoring Ireland's first century, while Frank's son Jimmy, was also called to Ireland's colours as a batsman.
Jack developed his cricket at Ennis College, a now long gone institution which produced several excellent cricketers. However he did not play for Dublin University while in residence there, playing instead some matches for Phoenix. His name was made, though, for the Ballinasloe Club, one of the oldest in Ireland, though JT Hurford, compiler of John Lawrence's Handbooks studiously ignored its progress, unless, of course, the Club's Secretary was dilatory in sending in annual details, a problem which Hurford certainly faced from other clubs. As it is the extensive researches of Stephen Doolan have revealed that it was through players such as Jack and his brother Frank that Ballinasloe was able to maintain its high reputation. As a 20 year old in 1866 Jack, who was an aggressive and free scoring batsman, often opening the innings, "led the charge" to bring victory over Gallen Priory CC from Ferbane, while in July 1870, he was prominent in the defeat of the Athlone Garrison, his dashing 54 aided by a more circumspect 58 from Robert Persee, helped set up a 153 runs victory.
Unfortunately Jack's one match for Ireland did not allow him to reveal his talents. Played as XXII of All Ireland against the All England XI it was the fourth and last meeting between Ireland and the famed professional "circus." Played at Rathmines the game was badly affected by rain which intervened for the final time when Ireland, who had contested the match well until their second innings, were 41-14 needing 128. That they had kept on level terms for so long was largely due to some fine batting by Pat Casey in the first innings, and the bowling of GF Barry and EH Moran, a northerner, prominent in both wings of NICFC. Jack himself caught the fearsome all-rounder George "Tear Em" Tarrant off Army officer WH Walrond in the first innings. Walrond, later Lord Waleran and British Chancellor of the Duchy of Lancaster, was one of those whose selection for the match was criticised by some parts of the press, who thought that Irish born / permanently resident players should have been chosen rather than " birds of passage." No such criticisms could be made of Jack's selection, but opening the batting he was bowled by left arm roundarmer JC Jemmy Shaw for 0. He did not bat during Ireland's panicky second innings display.
Away from cricket and from his profession as a civil engineer, John Kempster married Alice Augusta Walker at Ballinasloe in 1872. She was one year his senior, despite the 1901 Census which suggests that she was 19 years younger! She survived him and, living with her younger sister at the family home as the sole beneficiary of his will.