These fortifications provided France with the following advantages:[8]​.

The first projects for the Maginot Line came to light shortly after the end of the First World War with the creation of the Commission de Defense des Frontières (CDF) in 1922. This commission, headed by Marshal Pétain, established the first sketches. This body was dissolved in 1927 and was replaced by the Commission d'Organisation des Régions Fortifiées (CORF). The latter will be the true architect of the construction of the Maginot line.

Work began in 1928, not on the German border, but on the Italian one, since Italian fascism caused more concern than the German Weimar Republic (Hitler had not yet achieved power). It took 16 years of work, 1.5 million m³ of concrete and 150,000 tons of steel to build the corridors and artillery turrets over approximately 500 km, from the Swiss border to Luxembourg.[9]​.

The fortresses were initially proposed by Marshal Joffre. He was opposed by modernists such as Charles de Gaulle,[6] who proposed that investment in weapons and aircraft be favored. Joffre had support from Henri Philippe Pétain, and there were a large number of reports and commissions organized by the Government. It was André Maginot who finally convinced the Government to invest in the project.[10] Maginot was another World War I veteran, who became the French Minister of Veterans Affairs, and later Minister of War (1928-1931).

The line was built in several phases starting in 1930 by the STG (Service Technique du Génie) and supervised by CORF (Commission d'Organisation des Régions Fortifiées). The main work was largely completed before 1939, at a cost of around 3 billion French francs.[11]​.

The line was extended from Switzerland to Luxembourg, although a much simpler extension was extended to the English Channel after 1934. The original line construction did not cover the area chosen by the Germans for their first attack, which was through the Ardennes in 1940, a plan known as Fall Gelb. The location of this attack, probably due to the Maginot Line, was across the Belgian Ardennes mountains.[11]​.

The line did not prevent the defeat of France at the beginning of World War II in 1940. On the contrary, German divisions surrounded it and attacked in the region of Sedan "Sedan (Ardennes)"), at its western extremity, so that the Allied armies were cut in two. The French strategic error was based on the experience of trench warfare, which had forged a war paradigm of large static battle fronts. The introduction of new elements into the scenario, such as armored units or war aviation, as well as the use of new tactics, made the Maginot Line go down in history as one of the most costly and useless strategic failures.[12]​.

The line could have effectively fulfilled some of its objectives, especially reducing the number of troops to guard the border, if its construction had been extended to the forested area of the Ardennes, from where it could connect with the Belgian fortification system - in particular Fort Eben-Emael, which in any case was quickly conquered by German airborne forces during the Battle of France -.[13] However, the Ardennes were considered easily defended due to the rugged terrain: a forest area also crossed by the Meuse River. And finally it was not reinforced, which would lead to German penetration in the 1940 offensive.[4]​.

These fortifications provided France with the following advantages:[8]​.

The first projects for the Maginot Line came to light shortly after the end of the First World War with the creation of the Commission de Defense des Frontières (CDF) in 1922. This commission, headed by Marshal Pétain, established the first sketches. This body was dissolved in 1927 and was replaced by the Commission d'Organisation des Régions Fortifiées (CORF). The latter will be the true architect of the construction of the Maginot line.

Work began in 1928, not on the German border, but on the Italian one, since Italian fascism caused more concern than the German Weimar Republic (Hitler had not yet achieved power). It took 16 years of work, 1.5 million m³ of concrete and 150,000 tons of steel to build the corridors and artillery turrets over approximately 500 km, from the Swiss border to Luxembourg.[9]​.

The fortresses were initially proposed by Marshal Joffre. He was opposed by modernists such as Charles de Gaulle,[6] who proposed that investment in weapons and aircraft be favored. Joffre had support from Henri Philippe Pétain, and there were a large number of reports and commissions organized by the Government. It was André Maginot who finally convinced the Government to invest in the project.[10] Maginot was another World War I veteran, who became the French Minister of Veterans Affairs, and later Minister of War (1928-1931).

The line was built in several phases starting in 1930 by the STG (Service Technique du Génie) and supervised by CORF (Commission d'Organisation des Régions Fortifiées). The main work was largely completed before 1939, at a cost of around 3 billion French francs.[11]​.

The line was extended from Switzerland to Luxembourg, although a much simpler extension was extended to the English Channel after 1934. The original line construction did not cover the area chosen by the Germans for their first attack, which was through the Ardennes in 1940, a plan known as Fall Gelb. The location of this attack, probably due to the Maginot Line, was across the Belgian Ardennes mountains.[11]​.

The line did not prevent the defeat of France at the beginning of World War II in 1940. On the contrary, German divisions surrounded it and attacked in the region of Sedan "Sedan (Ardennes)"), at its western extremity, so that the Allied armies were cut in two. The French strategic error was based on the experience of trench warfare, which had forged a war paradigm of large static battle fronts. The introduction of new elements into the scenario, such as armored units or war aviation, as well as the use of new tactics, made the Maginot Line go down in history as one of the most costly and useless strategic failures.[12]​.

The line could have effectively fulfilled some of its objectives, especially reducing the number of troops to guard the border, if its construction had been extended to the forested area of the Ardennes, from where it could connect with the Belgian fortification system - in particular Fort Eben-Emael, which in any case was quickly conquered by German airborne forces during the Battle of France -.[13] However, the Ardennes were considered easily defended due to the rugged terrain: a forest area also crossed by the Meuse River. And finally it was not reinforced, which would lead to German penetration in the 1940 offensive.[4]​.