The Ministry of Health Act 1919 empowered the Minister of Health to discharge any of his functions in respect of Wales through a Welsh Board of Health, which was constituted under Section 5 of the Act and came into existence on 1 July 1919. It comprised a chairman, a medical member and an insurance member who had all been members of the dissolved National Health Insurance Commission for Wales which the board replaced. From September 1919 until 1924 the minister was also advised on the provision of medical and allied services in Wales by a Welsh Consultative Council, whose chairman was the Welsh member of the National Health Insurance Joint Committee.
During its lifetime various changes were made in the constitution of the board. In September 1919 its secretary became an ex officio member on his appointment as Administrative Officer for Public Health. From 1919 to 1922 the Housing Commissioner for Wales was a member, his office being discontinued in the latter year. In 1928 the posts of secretary and chairman were abolished and the membership of the board reduced to three, responsible for insurance, medical work and administrative matters respectively. The chairman was restored in 1930, but from 1934 there were only two members, the chairman and the medical member. Later the membership was again increased to four.
The board was purely deliberative and not executive, and its meetings were not frequent. Its chairman had the right of direct access to the minister in matters affecting the board as a whole, but the board had no authority over its individual members in their departmental capacities. The members were all officials of the Ministry of Health and were each responsible for certain aspects of the work of the board in consultation with the heads of the appropriate divisions in London and in accordance with departmental policy.
In July 1919 the board took over the staff of the National Health Insurance Commission for Wales, and in April 1920 it became responsible for most public health services in the principality. These did not, however, include port health work, medical inspection of aliens, vaccination and environmental health matters like water supply, sewerage and sewage disposal. Further functions were added later.
The administration of the new contributory pension scheme was undertaken by the board from its inception in 1925. In 1931 it was charged with the conduct of public health surveys and with control of poor law medical services in Wales; the remaining poor law services were added in 1937. In 1934 work in connection with the welfare of blind persons, in 1937 the provision of mortuaries and in 1939 of the General Inspectorate in Wales were similarly delegated.
In May 1940 functions relating to housing and town planning, private street works, the constitution and alteration of local government areas and a wide range of local sanitary and other services, including water supply, sewerage and sewage disposal, burial grounds, street lighting, public cleansing, river pollution and smoke abatement were transferred to the board.
After 1951 it continued to deal with medical functions in Wales, but its local government and environmental health work passed to the Welsh Office of the Ministry of Local Government and Planning together with its responsibility for civil defence. The board was dissolved on 1 April 1969 under provisions of the Transfer of Functions (Wales) Order 1969 (SI 1969/388), and its powers transferred to the Secretary of State for Wales.
The board employed its own administrative, medical and insurance staff, and Insurance and, after 1939, General Inspectorates. During the period in which it was responsible for local government and environmental health services it also had housing and engineering technical staff. The Welsh Hospital Board reported to it. It also worked closely with the Welsh National Memorial Association, a chartered body established in 1912 to promote measures against tuberculosis and whose main activity was the provision of sanatoria.