Schneider left Nieuport in late 1913.  With Schneider's departure, Gustave Delage (no connection to the Delage automobile company) took over as chief designer in January 1914.  He began work on a sesquiplane racer - a biplane whose lower wing was much narrower in chord than its top wing and relied on a single wing spar instead of the usual two. This aircraft was not ready to fly until after World War I had begun but, as the Nieuport 10, the type saw extensive service with the Royal Naval Air Service (R.N.A.S.) of the United Kingdom and with the French and Russian Flying Services. The performance of the Nieuport 10, and the more powerful Nieuport 12, which also served with the Royal Flying Corps (R.F.C.) was such that they were used as fighters. Nieuport developed an improved design specifically intended as a fighter - the Nieuport 11, which was regarded as the "baby" (bébé) of the 10, which it closely resembled, except in size.

Until the end of 1917, most of the company's output would consist of successive developments of this one design, with more powerful engines, modest increases in overall dimensions, and slightly more refined aerodynamics, until the line ended with the Nieuport 27. As horsepower increased, the "V-strut" Nieuports began to suffer from the limitations of the sesquiplane wing form, and required careful piloting to avoid the risk of wing failures. By March/April 1917 the design was technically outclassed by the newer twin-gun Albatros D.III, and although the process of replacement had already begun, Nieuport 27's would still be in front line service in the spring of 1918. Even while still in frontline service, Nieuports of all types were being used at French and American flight training facilities, with the bulk of production from 1917 onwards going to flying schools.

Some pilots, notably Albert Ball and Charles Nungesser preferred the Nieuport due to its sensitive controls and maneuverability.  Pilots Eddie Rickenbacker and Billy Bishop flew Nieuport aircraft to some of their first victories, with Bishop achieving his when the Nieuport 23 he flew was already obsolescent.

The next design, the Nieuport 28 was the first Nieuport fighter with two spars to both upper and lower wings but by the time it was ready for service the French had already chosen the SPAD S.XIII as their primary fighter. Due to a shortage of SPAD S.XIIIs, the first fighter squadrons of the United States Army Air Service (USAAS), used the Nieuport 28 on operations. While only in operational service with the USAAS for a short time, the Nieuport 28 was the first fighter to be used on operations by a U.S. Squadron.

The Nieuport fighters were widely used by the Allied air arms, and various models were built under licence in both Italy and Russia. In Italy, the modern firm of Aermacchi was originally formed as Nieuport-Macchi for the purpose of building various Nieuports under licence.  They started with the Nieuport IV, but built the Nieuport 10, 11, 17 and finally the post-war NiD.29 under license.  In Russia several companies, notably Dux, built Nieuports of several types including the IV, 10, 11, 16, 17, 21, 23 and 24bis.

On the morning of Friday, 8 August 1919, three weeks after the Paris victory parade in 1919 marking the end of hostilities in World War I, Charles Godefroy flew a "v-strut" Nieuport fighter through the large arch of the Arc de Triomphe in Paris. The event was filmed.

By the end of 1918, Nieuport had two new fighter types flying, the Nieuport 29 biplane and the Nieuport 31 monoplane both of which had evolved in parallel from the Nieuport 28. They differed from earlier Nieuports in having streamlined wooden monocoque fuselages, a 300 hp (220 kW) Hispano-Suiza engine, and dispensed with the vee-strut sesquiplane wing used previously. Specially modified Nieuport 29 and 31 aircraft set speed and height records, and the 31 was the first aircraft to exceed 200 mph (320 km/h) in level flight, in the hands of Joseph Sadi-Lecointe.

At this time, Nieuport became Nieuport-Astra, with the absorption of Société Astra, a company known for aerial balloons, though this name would not be used for long, before becoming Nieuport-Delage, in honour of the work of the chief designer, Gustave Delage, who had been running the company throughout the war years. Also at this time, Tellier (who built seaplanes) was also absorbed, and for a brief time the name Nieuport-Tellier was used.

Despite the many successes achieved with 29 and 31 in setting speed and altitude records, Delage quickly embarked on a new design (The Nieuport-Delage NiD.42) that was to provide the basis for a family of aircraft that would remain in service until the fall of France during World War II. This design first saw light as a shoulder wing racer (42S), then as single seat (42 C.1) and two seat fighters (42 C.2) for the French Air Force though none of these would see service. The Nieuport-Delage 52, a slightly improved NiD.42, entered service with Spain, and remained in service well into the Spanish Civil War, although by that time it was obsolete and was retired before the end of the conflict. The French bought large numbers of the 62 series (620, 621, 622, 629) which was also derived from the NiD.42 to equip the bulk of the French fighter units until replaced by newer designs in the late 30's. Despite being hopelessly obsolete, several French second-line escadrilles were still equipped with them during the invasion of France. The Nieuport-Delage NiD 38 and similar 39 were small airliners of which more than 37 were built. Other types were developed, the majority of which were one-offs or did not result in significant production.

The final aircraft developed by Nieuport saw much of their development done by successor companies. In 1932, as a result of the amalgamations taking place in the French aviation industry, Delage retired and Nieuport-Delage was briefly renamed Nieuport again, before merging with Loire Aviation to form Loire-Nieuport, which was reformed as SNCAO during the mergers in the French aircraft industry. SNCAO would eventually be merged into the massive conglomerate known as Aérospatiale, however, the records were burnt to prevent their falling into German hands during World War II. This step didn't prevent the Germans from charging several employees with espionage, as the last operational aircraft to carry the Nieuport name, the Loire-Nieuport LN.401 was a single seat, single engine retractable gear monoplane dive bomber with an inverted gull wing and a vague similarity to the Junkers 87.

Source: Wikipedia