If one attributes the mounted infantry to the creation of "Fischer's voluntary infantry company," as has traditionally been done, then one would have to wait until 1757 for the first units to be organized. Horsemen make their presence in the royal cavalry in 1776 with the creation of a mounted infantry squadron attached to each dragoon regiment. Our study commences with the "first truly" mounted infantrymen described by the 1779 ruling. Presented are those of 12 regiments from 1784, and the 26 who would fight during the Revolution, in addition to those from Valmy at Marengo... from the Constituent to the Consulat, without forgetting the voluntary units who would come to support the enlisted units. Volume 2 to follow will examine the regiments from the periods of the Consulat and the Empire.