The squadron motto, In omnibus princeps ("First in all things") reflects the squadron's status as the RAF's oldest unit, having been involved in almost every major British military operation from the First World War onwards...
No.1 Squadron was one of the first four squadrons of the Royal Flying Corps when it was formed on 13th May 1912. It took over its operation of the balloons, airships and kites from No.1 Airship Company, Air Battalion, Royal Engineers. When airships became the responsibility of the Naval Wing on the 1st January 1914, the squadron continued to operate at Farnborough until 1st May 1914, when it was redesignated the Airship Detachment, R.F.C. On the same day, a cadre for a new No.1 Squadron was formed at Brooklands but the outbreak of war in August resulted in its aircraft being taken over by the active squadrons destined to accompany the British Expeditionary Force to France.
Resuming training with available aircraft, the squadron completed training in February 1915 and early in March moved to France as a reconnaissance unit, beginning operations on 10th March. A few single-seat scouts were received during 1915 and the first practicable single-seat fighters, the Nieuport 17, arrived in March 1916 and were flown in small numbers. In January 1917, No.1 completely equipped with Nieuports and became a fighter squadron, converting to S.E.5a's in January 1918. For the rest of the war, it engaged in fighter patrols and ground attack duties over the Western Front. In February 1919, it was reduced to a cadre and in March returned to Britain where it was disbanded on 20th January 1920.
On 21st January 1920, No.1 Squadron was reformed at Risalpur on the North West Frontier of India. Initially it was designated a 'B' Squadron, with Sopwith Snipes but in May 1921 was moved to Iraq to join other elements of the RAF policing the desert areas. The squadron remained there until it was disbanded on the 1st November 1926. On the 1st February 1927, it reformed at Tangmere, equipped with the Armstrong Whitworth Siskin as part of the fighter defence of Great Britain. In February 1932 the squadron re-equipped with Hawker Furies, which flew until they were replaced by Hawker Hurricanes in October 1938.
With the declaration of war on 3rd September 1939, a long-standing agreement between Britain and France that would see the former rapidly despatch a substantial armed force to the continent, was evoked. The British Expeditionary Force has since arrived in France, the RAF being split into two parts. First, the Air Component of the B.E.F. (referred to by the Air Force as the "RAF Component") being comprised of four fighter squadrons , four Blenheim bomber-reconnaissance squadrons, and four Lysander army co-operation squadrons, all based in the Pas-de-Calais. The second, the Advanced Air Striking Force (A.A.S.F), comprising ten battle light bomber squadrons is based around Reims.
The Squadron left Tangmere for France on 7th September, and after a short stay at Havre, as part of the B.E.F.'s Air Component, joined up with No.73 Squadron to form No.67 (Hurricane) Wing attached to the A.A.S.F. The Squadron is now based at Vassincourt, near Bar-le-Duc, fifty miles east of Reims.