Department of National Defence
The Department of National Defence (DND) was created on 1 January 1923 through an amalgamation of the Department of Naval Services with the Department of Militia and Defence and the Air Board. DND was intended to reduce administrative costs among the three services, as well as improve the coordination of national security policies. The new single department DND oversaw the Royal Canadian Navy, the Militia (later Canadian Army), and the Canadian Air Force (later Royal Canadian Air Force).
Early efforts at integrating the services failed and the RCN, Militia, and RCAF maintained separate headquarters. During the Second World War, a Minister of National Defence for Air and a Minister of National Defence for Naval Services were appointed in May and July 1940 respectively. In 1946, DND reverted to having a single minister, whereby efforts were renewed at reducing duplication among the services.
In 1964, the position Chief of the Defence Staff was created, replacing the heads of the individual services as the nation's top military officer, and Unification merged the three services to form the Canadian Forces.
In the years following Unification in 1968, problems were identified in the management of DND, especially concern over capital acquisition programs and an apparent duplication of interests and involvement on the part of the Deputy Minister's Office, Canadian Forces Headquarters and the Defence Research Board. A Management Review Group was appointed in 1971 and directed to address and report on these concerns.
In a controversial October 1972 DND reorganization, the previously separate civilian and military branches in Ottawa were merged to form the single Department of National Defence Headquarters (NDHQ), with appointments being filled by both civilians and Canadian Forces officers, integrating the staffs of the Deputy Minister (DM) and the Chief of the Defence Staff (CDS).
This basic model of NDHQ, with management and control of DND and the CF based on the diarchy of the DM and CDS, endured to the end of the 20th Century and beyond.