I’ve always been facinated by the french canteen. Maybe it came about as a kid, watching movies like Beau Geste and being fascinated by french uniforms and equipment. The Bidon is either a 2-liter or 1-liter canteen, covered with horizon blue or later khaki wool cloth. Both types had two spouts, a large and small, that were stopped with either wood or cork which was secured to the canteen itself with string. Often two bidons were worn; in the assault, one bottle typically contained wine (pinard) mixed with water, the other coffee and tafia spirit. Many Americans chose to carry a french canteen due to their capacity.
I think that the French canteen defined the french Poilu of WW1. It was kind of iconic to the French soldier.
At the start of WWI the Metropolitian troops were using the 1 Litre Modèle 1877 Bidon, which was covered in dark blue cloth while those forces in North Africa were using the 2 Litre Modèle 1877 Bidon which was also covered in a dark blue cloth. The French military had thought that 1 liter was enough water to carry while on campaign as they could get re-supplied with water easily but as the war went into trench warfare re-supply became an issue and getting water to the front became difficult so then by 1915 ALL French forces started to get issued the 2 liter version.
Covers came in many different color and variations depending on the years they used, in 1914 dark blue was the norm; 1915 dark blue was still popular but as they were starting to go to a new horizion blue uniform, this color of cloth was also started to be used on the bidon themselves but other colors were also used with the ersatz type uniforms that were being used during this period such as brown courderoy, blue-gray or dark blue-gray. Colonial troops were starting to get their moutarde (khaki) uniforms during this period so covers were made in this color. Now during this period it was not uncommon for the bidons to be painted in a variety of colors listed above as well. In 1916 things started to become more uniform, horizion blue for metropolitan and moutarde for colonial troops, so covers were made in these cloth and issued which went all the way to the end of the war in 1918.