The school's motto is in French, Dieu et Devoir (English: ‘God and Duty’). This motto was formulated in 1911, 50 years after the school opened. The French language was chosen for the motto on the basis of the strong French influence in the school's early years.
All Hallows was founded in 1861. The school was the first permanent home of the Sisters of Mercy in Queensland, and is the oldest surviving secondary school. The School began a small House of Mercy at a site adjacent to Saint Stephen's Cathedral, and then the Convent obtained on Duncan’s Hill around 1889 -- Adderton House, constructed in 1858 by John Petrie for George Fullerton.
All Hallows' School, Brisbane" [https://web.archive.org/web/20070829052634/http://msea.mercy.org.au/resources/mercy/all_hallows_school.html]. Australasian Mercy Secondary Schools Association. Archived from the original (http://msea.mercy.org.au/resources/mercy/all_hallows_school.html) on 29 August 2007. Retrieved 8 September 2007.
"The All Hallows' Story" (https://web.archive.org/web/20110407114432/http://www.allhallows.qld.edu.au/prospectus/history/school_history.asp); Allhallows.qld.edu.au. Archived from the original (http://www.allhallows.qld.edu.au/prospectus/history/school_history.asp) on 7 April 2011. Retrieved 14 January 2012.
Mahoney, Jean-Marie, Dieu et Devoir: the Story of All Hallows' School, Brisbane, 1861-1981, Boolarong Publications, Brisbane, 1985.
All Hallows' Main Building at Duncan Hill, c. 1889. Photographer: A. Lomer & Co. Archive: John Oxley Library, State Library of Queensland. [https://commons.wikimedia.org/w/index.php?curid=12672170]