Frederick Baker was born at Whauwhaukauri, Hokianga, on 19 June 1908, the son of John Francis (Frank) Baker and his wife, Jane Robinson. His father was a bushman but subsequently became a dairy farmer. Baker was of Nga Puhi descent from his mother. He grew to six feet tall and had a dark complexion, brown eyes and dark hair. Educated at Rawhia School and then at Rawene District High School, he gained his proficiency examination in standard six and the public service entrance examination in 1924. He joined the Public Works Department at Whangarei on 1 October 1924 as a clerical cadet. From his first appointment he was noted as showing promise. He maintained a schoolboy interest in rugby and played for Waikato and the Bay of Plenty. In 1928 Baker was transferred to Hamilton, where by the end of 1931 he had completed his Professional Accountants' Examinations. In 1932 he passed the Australian Institute of Secretaries examinations (and became an associate of the institute in 1935). He transferred to the Audit Office in Wellington in January 1933 and assisted the audit of the State Advances Office. On 26 December 1933 at the Presbyterian church in Frankton, he married Edna Mavis Carrie, a dressmaker of Hamilton. There were two children of the marriage. In September 1935 his accounting ability was recognised when he joined the Mortgage Corporation of New Zealand.He became an inspector a year later after it had become the State Advances Corporation of New Zealand. He was later acting accountant in Auckland.
Baker had joined the Territorial Force in 1926, and was a sergeant by 1928 and a lieutenant in June 1931. He served in the mounted rifles in Northland and Waikato, but after moving to Wellington in 1933 he became a reserve officer as there were no mounted rifles units there. He maintained his interest in soldiering through the 1930s, and on 20 May 1939 requested, in view of the uncertain international situation, to transfer to the active list. He was unable to find a posting before the Second World War began, but by November was posted to the 28th (Maori) Battalion as its intelligence officer.
In July 1940, in England, he was promoted to temporary captain and took charge of Headquarters Company. He demonstrated his considerable organising ability in his arrangements for the battalion's embarkation to Egypt on 3 January 1941. In March the battalion was involved in the disastrous campaign to defend Greece against the Germans. Baker commanded the Reinforcement Company, which took heavy casualties. He himself was captured, but managed to escape. After 'finding a seaplane which he couldn't fly, a speed launch which he couldn't start, and a horse he couldn't catch' he was picked up by a Greek truck and taken to an embarkation point.
After rejoining the battalion in Crete he was involved in heavy fighting and took command of its A Company after both senior officers were lost. He was wounded but took charge of other walking wounded and led them ahead of the retreating battalion. He was among the troops taken off Crete by the Royal Navy. In Egypt he was transferred to the 25th Battalion as a company commander. He then rejoined the Maori Battalion as second in command with the rank of major. On 13 July 1942, after Lieutenant Colonel Eruera Love's death on 12 July, Baker was made temporary lieutenant colonel and given command of the battalion.
He was to command the Maori Battalion until 2 November 1942. During this time General Bernard Montgomery took command of the Eighth Army, to which the New Zealand Division belonged, and Brigadier Howard Kippenberger, the commander of the 5th New Zealand Infantry Brigade, decided to use the Maori Battalion in a pre-emptive strike against an anticipated German attack. It was the first offensive action Baker commanded. He led a patrol to check the route and identify the objective, the El Mreir depression. After one failed attack, the raid he led on 26 August was highly successful and was considered a model operation. He was later given the task of taking the northern edge of the Munassib depression and linking up with the 21st Battalion in a neighbouring depression. The Maori Battalion initially went beyond its objective into enemy territory and was in danger of being surrounded. After reorganisation by Kippenberger, the battalion reached its position on the right flank of the 21st Battalion and defeated an attack by German tanks.
The planning for the battle of El Alamein was now under way. Baker attended a conference on the proposed campaign and memorised the map details. At battalion headquarters he set up a sand tray, on which the battalion officers fought actions in preparation for the battle. Baker now demonstrated his attention to detail. The Maori Battalion was attached to a British brigade. The planning was careless and the locations of landmarks were inaccurate so that the force would have lined up over a mile south from where it should have been. Baker got his intelligence section to put down the starting-line tapes at the correct place. After considerable discussion he persuaded the other battalion commanders to move north into their correct positions. Half an hourinto the assault Baker was seriously wounded. He was appointed an immediate DSO for his aggressive leadership and was invalided home. The wounds, to his mouth and tongue, were severe and he spent almost a year convalescing and undergoing surgery to restore his ability to speak. In his four months of command he had taken the battalion through a series of highly successful operations.
Baker does not seem to have identified strongly with his Maori ancestry. He wrote about the Maori soldiers he commanded with detachment, even some initial scepticism. Yet he came to admire their fighting ability, and the rank and file of the battalion apparently regarded him as Maori: Ngati Porou officers writing to Sir Apirana Ngata in February 1943 begin by lamenting the loss of the two Maori colonels, Love and Baker. When the history of the battalion was being compiled, Kippenberger raised the question of Baker's Maori ancestry with Sir Bernard Freyberg and classified him among the Maori colonels.
Baker was appointed as director of the Rehabilitation Department in November 1943 by a government anxious to put rehabilitation on a proper footing. Based in Wellington, he was a member of the Rehabilitation Board, which aimed to see ex-servicemen placed in employment or provided with the means of earning a livelihood, and to see them suitably housed. It found housing by preferential allocations of state houses for over 17,000 personnel and housing loans for over 73,000. By 1963 there were 217,179 service personnel recorded with the board, for whom it also provided trade training, educational bursaries, settlement on the land or business loans.
At the height of the Rehabilitation Department's activity between 1946 and 1953 its annual expenditure averaged £19 million and it employed over 1,100 staff. Baker himself was very much at the centre of this activity. He was on all the executive and advisory committees of the board and provided the main co-ordinating link in the rehabilitation structure. He was also appointed to the Organisation for National Development, the Labour government's abortive attempt to provide for planning after the war.
Maori resented the way their soldiers had been treated by rehabilitation policies after the First World War, and the government had stated as early as 1940 that it would treat Maori and Pakeha ex-servicemen equally. It was Baker's responsibility to ensure that this happened. He accepted that a special organisation was needed for Maori and supported the establishment of the Maori Rehabilitation Finance Committee. The Rehabilitation Board used the Native Department, and later the Department of Maori Affairs, as its agent and Baker was insistent that the services to Maori reach the same standard as those for Pakeha ex-servicemen. When he was not satisfied that these standards were being reached he kept up a steady pressure to force changes. By this policy he honoured Ngata's promise that if Maori paid the price of citizenship they would receive its rewards.
In April 1954 the Rehabilitation Department was abolished and made a division of the Department of Internal Affairs. Baker remained its director but was also appointed to the Public Service Commission on 15 September 1954. He died of a heart attack in Wellington on 1 June 1958, survived by his wife and their daughter and son.