Formed in 1941 under the auspices of an agreement between the Polish Government in Exile and the United Kingdom, No. 317 "City of Wilno" Fighter Squadron was one of several Polish units integrated into the Royal Air Force during the Second World War. Initially based at RAF Exeter, Clyst Honiton, the squadron operated from July 1941 to April 1942, playing a vital role in the air defence of southern England.

Equipped first with Hawker Hurricane IIA and IIB fighters, and later transitioning to the formidable Supermarine Spitfire VB, 317 Squadron was tasked with offensive sweeps from June 1941 through September 1942. These operations targeted enemy positions across occupied France and Belgium, contributing to the broader Allied air campaign over the Channel.

Flight Lieutenant Szczesny, appointed commanding officer of ‘A’ Flight, led the squadron in daylight defence of Exeter—while nocturnal protection fell to No. 307 Polish Night Fighter Squadron. Under Szczesny’s leadership, 317 Squadron became an integral part of the newly formed Second Polish Fighter Wing, charged with safeguarding the southeastern approaches to England and the adjacent sector of La Manche (the English Channel).

The Wing’s offensive sorties often required pilots to land at coastal airfields mid-mission to refuel, a logistical challenge that underscored the intensity of operations during the summer of 1941. It was a defining period for No. 317 Squadron, solidifying its cohesion and combat readiness.

Later that year, the squadron distinguished itself in maritime operations, providing vital air cover for Allied shipping. To better support these missions, the unit relocated from RAF Exeter to RAF Bolt Head—a coastal satellite airfield in Devon. RAF Bolt Head featured two runways: one measuring 3,680 feet at a heading of 45°, and the other 4,200 feet at 120°, offering strategic access to the Channel and beyond.

The Squadron aircraft code was 'JH'.  

The squadron was disbanded on January 3, 1947 at RAF Portreath in Cornwall.