The building was built between 1915 and 1918 for an original cost of $282,051 Canadian dollars. The building was designed by T.W. Fuller (Department of Public Works Architect) and the project was supervised locally by Calgary architect Leo Dowler. The structure was actually built by A.G. Creelman Co. of Vancouver.
Construction began September 24, 1915 and according to some sources was held up by lack of bricks. Two brick factories, one in Redcliff and one in Montgomery were built for the specific purpose of providing the bricks to complete the project. The building was completed in 1917. During the Second World War, several wooden huts were built to accommodate the large number of Calgary soldiers mobilized for the First World War.
In 1939, a large Recreation Hall was also built adjacent to the armouries. In 1941, the hall burnt down.
The armoury for a time was home to a Permanent Force squadron of Lord Strathcona's Horse, but is most commonly associated with the Militia units in Calgary. Over the years, several units have been based at Mewata including South Alberta Light Horse, 19th Alberta Dragoons, King's Own Calgary Regiment, the Calgary Highlanders, and 746 Communications Squadron.
During the First World War, Mewata was used served as an induction and training centre and a demobilization depot for returning soldiers.
In addition to military uses, other groups and organizations have always used the armoury including a military ball for the Prince of Wales in 1919, the scene of a verbal confrontation between William Aberhart and Major Douglas founder of Social Credit. The Calgary City Police and Calgary Fire Department have often used it for training purposes. In 1975 prior to the Grey Cup parade twenty marching bands were marshalled in the drill hall.
The building was declared a Provincial Historic Resource on 11 November 1979 and a National Historic Site on 11 May 1991, only the fourth building in Calgary to receive a national designation.
Lieutenant Brian S. King, CD, Curator of the Regimental Museum, received permission from 41 Canadian Brigade Group to place a vehicle in front of Mewata Armoury, after discussions in the Museum in 1997. This form of homage is common in other armouries and military bases across Canada. Lieutenant King sought out collectors in order to obtain an appropriate vehicle, and negotiations with the Canadian War Museum yielded this fully restored carrier, from the collection of Jack Guthrie, a notable Calgary vehicle collector. The concrete pad for the carrier was donated by BURNCO and the plaque purchased by the Regimental Funds Foundation through a grant from the Royal Alberta United Services Institute. The markings were researched and painted by Corporal Michael Dorosh, at that time a clerk with battalion headquarters. The plaque was unveiled by Second World War veterans Sergeant Clarence "Ken" Crockett, DCM and Lance Corporal Floyd Rourke, DCM.