The Louis d'Or is any number of French coins first introduced by Louis XIII in 1640. The name derives from the depiction of the portrait of King Louis on one side of the coin; the French royal coat of arms is on the reverse. The coin was replaced by the French franc at the time of the revolution and later the similarly valued Napoleon.
The Louis d'or under Louis XIV was similar in most respects to its predecessor and had a dimension of +/- 25 mm, and a weight of 6.75 g.
Louis XIV (5 September 1638 – 1 September 1715), known as Louis the Great (Louis le Grand) or the Sun King (Roi Soleil), was a monarch of the House of Bourbon who reigned as King of France from 1643 until his death in 1715. Starting at the age of 5, his reign of 72 years and 110 days is the longest recorded of any monarch of a sovereign country in European history. In the age of absolutism in Europe, Louis XIV's France was a leader in the growing centralization of power. The coinage of Louis XIV is much appreciated by numismatists.