Question: The 76-mm air-defense gun M1914/15 was an anti-aircraft gun used during a war that lasted during which dates?

Context paragraphs:
QF 3-inch 20 cwt: The QF 3 inch 20 cwt anti-aircraft gun became the standard anti-aircraft gun used in the home defence of the United Kingdom against German airships and bombers and on the Western Front in World War I.  It was also common on British warships in World War I and submarines in World War II.  20 cwt referred to the weight of the barrel and breech, to differentiate it from other "3 inch" guns (1 cwt = 1 hundredweight = 112 lb, hence the barrel and breech together weighed 2250 lb).  While other AA guns also had a bore of 3 inches, the term "3 inch" was only ever used to identify this gun in the World War I era, and hence this is what writers are usually referring to by "3 inch AA gun".

20 ITK 40 VKT: 20 ItK 40 VKT or "20 mm dual anti-aircraft cannon model 1940 manufactured by VKT" was a Finnish light anti-aircraft gun designed by the Finnish gunsmith Aimo Lahti.  As the only multi-barrel 20 mm anti-aircraft gun 20 ItK 40 VKT was the most effective 20 mm air defence weapon used by the Finnish Army during World War II.  A total of 174 guns were built, used in training until the 1970s and kept in reserve until 1988.  The gun received the nickname "Vekotin" (gadget) from Finnish soldiers.  The nickname was reached by adding to the abbreviation of manufacturer, VKT.

Type 96 25 mm AT/AA Gun: The Type 96 25mm Gun (九六式二十五粍高角機銃 , Kyūroku-shiki nijyūgo-miri Kōkakukijū ) was an automatic cannon used by the Imperial Japanese Navy during World War II.  A local built variant of the French Hotchkiss 25mm anti-aircraft gun, it was primarily used as an anti-aircraft gun in fixed mounts with between one and three guns, but was designed as a dual-purpose weapon for use against armored vehicles as well.

Type 11 75 mm AA gun: The Type 11 75 mm anti-aircraft gun (十一年式七糎半野戦高射砲 , Jyūichinen-shiki nana-senti-han Yasen Koshahō ) was an anti-aircraft gun used by the Imperial Japanese Army after World War I.  The Type 11 designation was given to this gun as it was accepted in the 11th year of Emperor Taishō's reign (1922).  It was the first anti-aircraft gun in Japanese service, but only a small number were produced, and it was superseded by the Type 14 10 cm gun and the Type 88 75 mm gun in active service before the start of World War II.

76 mm air-defense gun M1914/15: The 76-mm air-defense gun M1914/15 (Russian: 3" зенитная пушка обр.  1914/1915 года ) was the first Russian purpose built anti-aircraft gun.  Adopted during World War I, the gun remained in production until 1934.

Type 88 75 mm AA Gun: The Type 88 75 mm AA Gun (八八式七糎野戦高射砲 , Hachi-hachi-shiki nana-senti Yasen Koshahō ) was an anti-aircraft gun used by the Imperial Japanese Army during the Second Sino-Japanese War and World War II.  The Type 88 number was designated for the year the gun was accepted, 2588 in the Japanese imperial year calendar, or 1928 in the Gregorian calendar.  It replaced the earlier Type 11 75 mm AA Gun in front line combat service, and at the time was equal in performances to any of its contemporaries in western armies and was considered capable of handling any targets the Japanese army was likely to encounter on the Asian mainland.  Although it was soon overtaken by improvements in aircraft technology and was lately obsolete by 1941, it continued to be used on many fronts until the end of the war.

Bofors 57 mm m/54 anti-aircraft gun: The Bofors 57 mm m/54 was a wheeled automatic anti-aircraft gun for land based use produced by Bofors and developed from the similar Bofors Model 1950 57 mm shipboard anti-aircraft gun.  The gun was developed in the 1950s and fielded by the Belgian and Swedish forces.  In Swedish service, the gun was known as the "57 mm lvakan m/54".

45 mm anti-aircraft gun (21-K): The 45 mm anti-aircraft gun (21-K) was a Soviet design adapted from the 45 mm anti-tank gun M1932 (19-K).  This was a copy of a 3.7 cm German weapon designed by Rheinmetall that was sold to the Soviets before Hitler came to power in 1933 that had been enlarged to 45 mm to reuse a large stock of old 47mm ammunition.  It was used by the Soviet Navy to equip almost all of their ships from 1934 as its primary light anti-aircraft gun until replaced by the fully automatic 37 mm "70-K" gun from 1942 to 1943.  It was used in World War II and during the Cold War as the Soviets exported their World War II-era ships to their friends and allies.  However it was not very effective as its slow rate of fire and lack of a time fuze required a direct hit to damage targets.

World War I: World War I (WWI or WW1), also known as the First World War, the Great War, or the War to End All Wars, was a global war originating in Europe that lasted from 28 July 1914 to 11 November 1918.  More than 70 million military personnel, including 60 million Europeans, were mobilised in one of the largest wars in history.  Over nine million combatants and seven million civilians died as a result of the war (including the victims of a number of genocides), a casualty rate exacerbated by the belligerents' technological and industrial sophistication, and the tactical stalemate caused by gruelling trench warfare.  It was one of the deadliest conflicts in history, and paved the way for major political changes, including revolutions in many of the nations involved.  Unresolved rivalries still extant at the end of the conflict contributed to the start of the Second World War only twenty-one years later.

M42 Duster: The M42 40 mm Self-Propelled Anti-Aircraft Gun, or "Duster", is an American armored light air-defense gun built for the United States Army from 1952 until December 1960, in service until 1988.  Production of this vehicle was performed by the tank division of the General Motors Corporation.  It used components from the M41 light tank and was constructed of all-welded steel.

Supporting paragraphs: 76 mm air-defense gun M1914/15 World War I
Answer: 28 July 1914 to 11 November 1918