Following the cessation of World War 2, society quickly attempted to become as normal as possible as quickly as possible. Athletics competition was resumed in Brisbane, and the Harriers attempted to reform. However,
The Thompson Estate Harrier's Amateur Athletic Club was founded by interested men of the district of Thompson Estate, Junction Park, Annerley, Stones Corner, Coorparoo and Woolloongabba.
Messrs F. W. Nissen (Vice-President of the Queensland Amateur Athletic Association), James A. Donnan and John Innes Brown called a meeting of young men at the residence of Frederick William Nissen on 6th October, 1900.
At this meeting, the members of the committee and officials were elected, with Mr. Joseph Allen being the inaugural President, Mr. W. C. Anderson the inaugural Secretary, andMr. J. A. Donnan the inaugural Treasurer, while the first Club Captain was Michael Waterman. Other members of the first Committee were Frederick William Nissen, Walter C. Pritchard, F. Higginbotham, F.G. Jutsam, W. Stringfellow, J. Brown Sen., Allan Innes, J. Hourigan and James McHugh.
After the exciting period of the 1920's, the performance of the club in the 1930s was a reflection of the conditions in society in the 1930s - depression, tension and war.
The term "The Roaring Twenties" could easily apply to Thompson Estate Harriers Amateur Athletic Club during the 1920's. The Harriers were the Champion Club of Queensland in 1920, 1921, 1923, 1925, 1926, and 1929 - a remarkable achievement; R. W. Cook (1921) and H. V. Scouller (1923) were named Champion All-Round Athlete of Queensland; G. Lewis won the first ever Queensland Decathlon Championship; Thompson Estate Harriers won the Wallace Bishop Cup for Champion Indoor Games Club of Queensland in 1923 and 1924; the Club also won the Cross Country Championship of Queensland in 1920 and was runners-up in 1921 and 1923 and third in 1922 and 1929; the juniors won the title of Most Successful Junior Club of Queensland in 1920, were runners-up in 1927 and were third in 1926.
The 1940's began with the Harriers experiencing their second period of war, with the inevitable results of more members enlisting, and athletic competition being limited.