Alfred Thomas Carroll (Kara) was born at Wairoa, in northern Hawke’s Bay, on 24 August 1890, the youngest of three children of Thomas Carroll, a farmer, and his wife, Mako Kaimoana. At an early age he became known as Turi, after an ancestor, Turiparera. His father was one of eight children of Sydney-born Irishman Joseph Carroll and his wife, Tapuke, a Ngati Kahungunu woman of high rank, through whom the family land at Huramua was acquired. One of Thomas's brothers was Sir James Carroll. Turi was descended from Te Kapuamatotoru and Te Whewhera through their son, Tiakiwai.
Turi's parents arranged for their children to receive their first schooling at the Huramua homestead (sometimes called Hurumua), and Turi later attended Wairoa School. When his father died in 1904, his uncle, James Carroll, recognised qualities of leadership in Turi, and needing an heir in his many political and economic ventures, he arranged for him to receive a better education. After spending 1905 at Wanganui Collegiate School, he went to Te Aute College. In 1909 he began studying for a diploma in agriculture and animal husbandry at the Canterbury Agricultural College. A keen sportsman, he represented the college at cricket and rugby. He graduated in 1911, then took over management of the 2,200-acre family farm.
During the First World War Carroll took an active part in recruitment for the Maori Contingent. Although initially turned down for active service because he had lost the sight in his left eye, he went overseas in 1917 with the New Zealand Expeditionary Force. He became a sergeant and was wounded just before the end of the war. He returned to New Zealand in 1919. In the same year, he played in the Pioneer (Maori) Battalion rugby team.
On 4 March 1922, in Wairoa, Carroll married Parehuia Shrimpton, the daughter of Atamira Haeata and her husband, Walter Shrimpton. The couple were to have one daughter, Mako, but brought up many other children.
Like his uncle, Turi felt a strong need to be bicultural, and to use the skills and knowledge gained in the Pakeha world for the benefit of Maori. Unlike his uncle, however, his political involvement was initially mainly at the local level. In 1926 he was elected to the Wairoa County Council to represent the Waiau Riding. At the time it was rare for Maori to be elected to such a body. Carroll remained on the council until 1959, serving as chairman from 1938. He was also elected to other local bodies: the Wairoa Hospital Board, Electric-power Board and Harbour Board.
As well as running the Huramua station, Carroll was active in a number of farming organisations. He served on the board of the Wairoa Co-operative Dairy Company, and was chairman in 1933–34. He was a member of the Wairoa Farmers’ Union, and chairman of the Wairoa Agricultural and Pastoral Association. He was also chairman of the Maori incorporated blocks in the Wairoa district and believed that the shareholders should retain and develop their land. His work in raising the standard of farming in the area earned him a Bledisloe Medal in 1940.
Carroll was indefatigable in his work for the Maori people. He worked with Apirana Ngata to provide farming schemes for Maori. From 1928 he served on the Kahungunu Maori Council. He played a prominent role in planning and financing Takitimu, a carved meeting house at Waihirere marae, which was completed in 1938 as a memorial to Sir James Carroll. When the Young Maori Conferences were held in 1939 and 1959, to work out practical programmes to assist Maori development and welfare, he attended the first and was president of the second. Mindful of the high incidence of tuberculosis among Maori, he was instrumental in forming a tuberculosis association in Wairoa. He was also a member of the New Zealand Maori golf and lawn tennis associations.
After the Second World War, Carroll’s concern for the welfare of returned Maori soldiers led him to serve on the local rehabilitation committee. He sold 1,700 acres of the family property to the Native Department for use as a training centre for Maori returned servicemen. When they had gained farming certificates they became eligible to enter ballots for farms. The Huramua land was divided into 14 farms, and many trainees were settled there. In 1946 Carroll made over the remainder of his farm to his daughter and son-in-law.
With the passing of the Maori Social and Economic Advancement Act 1945, Carroll became a member of the Kahungunu Tribal Executive. In 1949 he was supported by Peter Fraser, the prime minister and minister of Maori affairs, in setting up the East Coast Maori Trust Council, which in 1954 handed over control of the trust lands to the Maori owners. In 1949 Carroll stood unsuccessfully for the Eastern Maori seat as a National Party candidate.
Carroll was made an OBE in 1952, and was knighted in 1962. From around this time, he became involved with various national organisations. He was a member of the Maori Education Foundation, and was trustee for the Mitchell Scholarship, established by J. H. Mitchell from the proceeds of his book Takitimu to enable students to attend secondary school. In June 1962 he was elected president of the New Zealand Maori Council of Tribal Executives. This became the New Zealand Maori Council in January 1963, and he retained the position until 1967. While president he was spokesman for the Maori people at the Waitangi reception during the royal visit of 1963. His role on the council was dogged by increasing conflict among younger Maori leaders: he was regarded as exemplifying a rural, conservative style of tribal leadership, which the educated, professional leaders of the 1960s found increasingly problematic, and overly accepting of Pakeha goals.
A devout Anglican, Carroll was a member of the diocese of Waiapu synod for 20 years, and was a people’s warden of the Wairoa–Mohaka Maori pastorate. As a long-serving member of the Wairoa College board of governors, he proposed the motto 'Kia mataara’ (Be alert), for the school. He was a foundation member of the Rotary Club of Wairoa, and served as president in 1949–50. With other members of Ngati Kahungunu and Tuhoe he signed an agreement with the government in September 1969 that leased the bed of Lake Waikaremoana to the Urewera National Park Board.
Carroll’s wife, Parehuia, who had supported him in all his undertakings, died in 1965. After a bad fall at the age of 80, when he broke his hip, Carroll was cared for by his daughter, Mako. The committee meetings of the land incorporations were subsequently held at his home. Sir Turi Carroll died at Huramua station on 11 November 1975. He lay in state on the Taihoa marae, where hundreds came to pay their respects, before being taken to the Takitimu marae for the funeral service. The cortège following the hearse to the family cemetery was over a mile long.