With the First World War having already started in the East of Europe and Germany mobilizing its troops, France in 1914 declared the order to mobilize 3,000,000 men from the 2nd to 18th of August 1914.
The general mobilization in France begins.
Since the end of the Franco-Prussian War in 1871, the French military system was changed several times. As the army followed a system of conscription, the majority of men serving were not professional soldiers. In 1913, the law Barthou decreed that all men could be called for a period of 3 years and no longer 2 years (30 years ago, the military service lasted 5 years). The legislation before the First World War was that every man aged 21 (age of adulthood at the time) spent three years in the army until their 23rd birthday. Men were then passed in the reserve forces for a period of eleven years.
With the various European powers mobilizing their troops in July (Russia, Serbia, Austria… etc) The 30th of July 1914, France’s intelligence and Commander-in-Chief Joseph Joffre warned in vain the Ministry of War that Germany would soon gather their troops to the borders and that it was necessary to quickly apply the Plan XVII. It was the plan of mobilization in 1914 which would permit to increase the military forces by calling the reserves and transporting the troops to the borders of the country.
The intelligence was right, the 31st of July, Germany closed its borders and entered a state of war. The day after, France announced to the German ambassador Wilhelm von Schoen that it would not remain neutral in a war between the Russian and German Empires. The French government accepted to start the order of General mobilization. To hours after, Germany did the same.
After the order was made, thousands of telegrams were sent to the heads of corps, to prefects and mayors. The Gendarmerie had the task to announce the news to the villages in the countryside and the tocsins rang their bells in the churches and cathedrals and posters stuck on the walls of all the towns of France.
The first poster was displayed on the 1st of August 1914, at 4:00 pm between the Place de la Concorde and the Rue Royale in Paris.
The mobilization was divided in three times, the call, the transportation and finally the start of the operations. 880,000 men were already in the active army (those who were doing their military service at the start of the war) before the arrival of the others. 2,200,000 reserves and 700,000 men from the territorial forces. Other men were called in the following days. People were also allowed to voluntarily engaged themselves in the army, should they be aged 17 or more. Around 71,000 men from Poland or Alsace-Lorraine and many other nations are said to have freely joined the army. Many students in military schools (such as Saint-Cyr or the Naval School) are accepted and made non-commissioned officers. According to historian Dominique Lejeune, the government had predicted that 13% of the requested men would wilfully disobey ( act of insubordination ) the order of mobilization but the number was very much lower, around 1,5%.
In 1914, France had a total population of 39 million inhabitants. The 30th of September, 3,986,000 men had been called to serve in the First World War. In two weeks, 686 battalions of Infantry saw their number rise to 1636, the 54 divisions in metropolitan France and the colonies of North Africa were 94 at the end of August.
During the war, between 7.9 and 8 million men were mobilized for France out of which 1,500,000 died and 4,900,000 wounded. Between 70,000 and 98,000 of the casualties for France were soldiers from the colonies, most of them from French Algeria and French Indochina.