Historical colours, standards and guidons

During Middle Age, the units had not really colours. They got often the heraldry of their lord. The armies got the fleurdelisé, a kind of French national flag : blue with lys flowers, because lys flowers were the symbol of France and of the King of France, until the 19th century. The King of France had also an official battle standard, the Oriflamme : a special flag, red with gold, and the motto "Montjoie Saint-Denis". When the king went to war, he had to take the oriflamme in Saint-Denis, near Paris. The knights, as lords, got their own colours (the member of the capetian dynasty were recognizable because of the lys flower on their family heraldry). The French field units got a white cross, called "Croix de France" (Cross of France). The English got a red cross.

The French colours of the Ancien Régime got the same design : a white cross, the Cross of France (vertical cross, but sometimes it was a St Andrew's cross, like the "Royal Deux Ponts" Régiment's flag). The rest of the standard was depending of the regiment. Often, the Cross of France divided the flag in four equal quarters. The quarters could have the same colour (specially for the Marine troops's flags). Sometimes, there were two colours : the top-left and the bottom-right quarters of one colour, the top-right and the bottom-left of another. In the most part of the time, lys flowers were on the Cross of France, with an inscription or a motto. The regiment often got the name of their province : Picardie (the oldest regiment of Europe), Normandie, Piemont, Provence... but were also called with special names, like "Régiment de la Reine" (Queen's regiment), which had a dark green and black quartered flag, with the cross of France. Each regiment had its flag. The colonel, at the head of the regiment, had a special flag : it also had the white Cross of France, but the four quarters were white too (white was the colour of the French monarchy). The actual flag of Quebec has exactly the design of the French colours of this time.

In 1794, the French Army was reorganised following the Revolution. Regiments were renamed demi-brigades, with three battalions in each. The 1st Battalion of each was raised from the volunteers, while the 3rd Battalion were conscripts. These two received identical colours. The 2nd Battalion meanwhile was formed from a regiment of the old Royal Army, and received a different colour from the 1st Battalion. The colours of all of the 2nd Battalions were identical to each other (except for the demi-brigade's number), while the 1st Battalions all received different colours.

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Wikipedia