In Edmonton, Brown went to work as an assistant to C.W. Mathers, Edmonton’s first photographer. Three months later on July 1, 1904, Brown bought the rights to Mathers’ portrait studio and in 1905 the studio expanded into the Ernest Brown Company Ltd. Years later in 1912 the Ernest Brown Block was built. Shortly after World War I, however, the demand for photographic services declined and Brown’s business was seized in 1920. In 1926 he moved to Vegreville where he set up another small photographic studio. He continued to maintain an Edmonton connection through his friend and associate, Gladys Reeves, and returned to Edmonton in 1929 to help her establish her own studio called The Art League.

In 1933 Brown established the Pioneer Days Museum in Edmonton, which operated until 1939. The principal aim of the museum was to educate children and teachers about the pioneer heritage of Alberta. Brown wrote many articles to document the historic photographs that were used as exhibits. With the help of Gladys Reeves, he also developed the “Birth of the West” photographic history series, which was used as the basis for illustrated lectures given to schoolchildren.

During his lifetime Ernest Brown acquired a number of historical photographs, including C.W. Mathers’ collection of archival negatives. This collection included not only Mathers’ own negatives dating from 1895, but also many of those of the early Calgary photographers, Boorne and May. Brown also had an interest in politics and in 1921 he was nominated candidate for the Independent Labour Party. He helped to organise political demonstrations on behalf of the unemployed and published a short-run reformist newspaper called The Glow Worm.

Ernest Brown died on January 5, 1951.

The Provincial Government of Alberta stored many of the manuscripts and items from the Pioneer Days Museum when Ernest Brown vacated Haddon Hall early in October 1939. In 1947 an agreement was reached between Brown and the Provincial Government for the sale of this material and the photograph collection to the government. For many years it remained in the custody of the Department of Economic Affairs. In 1962 these records were transferred to the Museum and Archives Branch of the Provincial Secretary's Department. On the appointment of a Provincial Archivist in 1965, the papers were then transferred from the Human History Division to the Provincial Archives of Alberta.

In 1968, another accession of records was transferred to the archives from the Film and Photographic Branch of the Department of Industry and Tourism at the Provincial Government of Alberta. The archives then received more of Ernest Brown's records from the Legislative Library in Edmonton in 1970. In 1974 another accession of records arrived at the archives as part of Gladys Reeves' estate. A local Edmonton man donated more Ernest Brown records to the archives in 1976. In 1979 a time capsule that had been deposited in the Legislature Building by Ernest Brown was discovered and given to the archives. In 1990 Norma Brown donated an accession of records to the archives.

In 2008, Roy and Lavon Holgate donated a photograph that was accessioned in 2009. The Holgates received the photograph from Jean McCormack, the daughter of a Mr. and Mrs. Dickson as identified in the inscription on the back of the photograph.

The fonds has been divided into the following series: Items regarding Boorne, May and Mathers; Personal and business papers; Political papers; Photographic studios’ records; Pioneer Days Museum records; Personal writings; Notes and research material; Newspapers; Periodicals; Printed books; Travel brochures and directories; Photographic material; Maps; Paintings; and Time capsule. Many of these series have been further divided into sub-series.