Historians once theorized that a coat of arms enabled a knight to be recognized by his followers during battles. The knights bore the emblems on his shield, then on his tunic (called tabard or surcot) which was the "cotte d’armes". That is the reason why the heraldic emblems were called in English: "Coat of Arms". The prestigious "College of Arms" founded in 1484 by Richard II still exists in England and decides who has the right to bear such or such Coat of Arms.
Heraldry has been defined as the art of blazoning, assigning, and marshalling a coat of arms. The word "Heraldry" is derived from the German "heer" — a host, an army — and "held" — a champion. The term "blason," by which the science of heraldry is denoted in French, English, Italian, and German, is probably derived from the German word "blazen" = to blow the horn. Whenever a new Knight appeared at a tournament, the herald sounded the trumpet, and as the competitors attended with closed visors, it was his duty to explain the bearing of the shield or coat-armour belonging to each. This knowledge of the various devices and symbols was called Heraldry, and as the announcement was accompanied with the sound of a trumpet, it was termed "blazoning the arms" (source : J-B Burke, "the General Armory")
The Coat of Arms of the City of Crest
In the 10th Century, a wealthy and powerful family, the Arnauds, settled in the region and had their castle built close to the Roman tower. The walls delimited a little city which was called "Crista Arnaldorum" (Crête des Arnaud) and later Crest Arnaud.
The Coat of Arms of the city of Crest are: "Silver chief headed with three red cockscombs, blue with the square golden windowed tower, doored and sand masoned, green terrace with a big C "Crista d’or" (Golden crest).
The only still existing example in Crest bears the date of 1530. In the old days, it was embedded in the corner of the old schools house, rue des Ecoles.
The Coat of Arms of the Poitiers
In 1165, after marriages, sharing, exchanges and loans, the Poitiers inherited part of the Arnauds’ property. For 250 years, from Guillaume 1er to Louis II (the first and the last earl of the Poitiers dynasty), there were endless fights between them, lords of Valentinois and Diois, and the Bishops of Valence and Die in regard to land, castles and towns they had owned jointly since 1226. This war, called "Guerre des Episcopaux" (Episcopal war), finally ended with the victory of the Poitiers who became the owners of two castles in 1358. They had a fortified citadel built with surrounding walls and doors which, year after year, were destroyed in order to facilitate the traffic.
The "Porte St André" still remains. It was also known as "Porte des Ecus du Diable" from the coat of arms of the Poitiers : "d’azur à six besants d’argent, trois, deux, et un, au chef d’or". (Blue with six silver besants, -three, two and one, with a golden chief). Those were inlaid above, inside and outside of the Porte St André. The ones inside seem to have disappeared recently and the ones outside have been destroyed. There are unfortunately no other examples.
The Coat of Arms of the Princes of Monaco
Honoré de Grimaldi, Prince of Monaco, had been very helpful to the French King, Louis XIII. So the latter, in 1641, contracted (Traité de Péronne) to allow the Princes 80,000 livres in the form of land in Dauphiné, Auvergne and Provence. So doing, he also gave the seneschalsy of Crest and the people of the city became the vassals of the Princes of Monaco. On the walls of the old prisons they owned, you can still see their Coat of Arms carved in stone. They are "d’argent à quinze fusées de gueules" (silver with fifteen red gules) surrounded by a moulding and topped by a prince’s crown.
The Arms of the Dauphiné united to France
They are carved in a very fine and hard white stone, surrounded by both the ribbons of St Michel and the Holy Ghost and topped by the Royal Crown. They were on a house which used to stand on the former "Place de l’Ancien Hôpital" commonly called "Place aux Blés", nowadays "Place Frédéric Mistral". In 1860, these Arms were embedded in the mantelpiece of the fireplace in a painter’s workshop converted into a private house library.
Those are the Arms which were always used by the French Dauphins.