​425 Squadron formed up on 25 June 1942 in Yorkshire, England. Its designation as the "First French Canadian Squadron" and its lark emblem, "Les Alouettes", made it a special squadron and it accordingly adopted the motto "Je te plumerai" ("I shall pluck you"). 425 Squadron, flying Wellingtons, Halifaxes and Lancasters, carried out over 287 bombing raids and earned more than 190 decorations during World War Two.
The order carried unprecedented significance in that its heading included after the squadron number the words "French-Canadian". This made the unit unique in RCAF history. Designated No. 425, it actually came into existence three days later at Dishforth, Yorkshire, as a unit of No. 4 Group. Given its operational baptism on the night of 5th/6th October, the squadron carried the war to the enemy until 26th/27th April 1943, after which it became non-operational pending a move to North Africa. Since 1st January 1943, it had been part of No. 6 Group.
 
Like many other squadrons at the time, 425 was decommissioned at the end of the war. It was reactivated in 1954 at St-Hubert, Quebec, equipped with the CF-100, the last Canadian-designed and built fighter. Its new role was that of all-weather fighter interceptor within the North American Air Defence Command (NORAD). In 1961, 425 Squadron was re-equipped with the CF-101 Voodoo at Namao, Alberta.
 
In July 1962, the Alouettes finally settled at the Bagotville base. Since then, the squadron has retained its fighter interceptor role in NORAD. A new era dawned in 1985 when it re-equipped with an ultra-modern aircraft, the CF-18 Hornet. 425 Tactical Fighter Squadron is an integral part of NORAD and of the North Atlantic Treaty Organization (NATO). In peacetime, the squadron's fighters provide continuous surveillance of the East Coast of Canada. In addition, it must be ready for rapid deployment anywhere in the world in support of NATO or contingency operations.