Jack Hemi was the oldest son of Hineipikitia-ki-te-rangi (Piki) Reiri, of Te Whiti, and her husband, Paraikete (Blanket) Hēmi. There were thirteen children in the family. Hemi attended Te Whiti School. He worked at a freezing works and, when his father died in 1936, Hemi assumed responsibility for his mother and four siblings.[3] Of Māori descent, he identified with the Ngāti Kahungunu and Rangitaneiwi.
Rugby union career
Hemi played rugby union for the Gladstone club before moving to the Featherston club and first represented Wairarapa in 1933, aged only 18. He played for New Zealand Māori in 1934 and toured Australia with the team in 1935. He was also an All Blacks trialist in 1935.[3]
He toured Australia in 1938, slotting a goal against Queensland from 17 yards behind the halfway line. Hemi toured Great Britain in 1939, but World War II ended the tour without a test match being played.[3] Exempt from War duty Hemi continued to play for Manukau.[4] In 1941 he scored 206 points for Manukau in all competition matches which was comfortably a record in Auckland Rugby League senior football to that point. He scored 12 tries, and kicked 59 conversions along with 26 penalties during the season.
In 1945 he represented Wellington alongside his younger brother, Lou.[3]