masc. proper name, from French Louis, from Old French Loois, probably via Medieval Latin Ludovicus, a Latinization of Old High German Hluodowig, literally "famous in war" (cognate with Clovis; for etymology see Ludwig).
As the name of a French gold coin 17c.-18c., short for Louis d'or, from the French kings of that name (originally Louis XIII) pictured on the coins. Louis-Quatorze (1855) refers to styles reminiscent of the time of King Louis XIV of France (1643-1715).
<a href="https://www.etymonline.com/word/Louise">Etymology of Louise by etymonline</a>
Harper, D. (n.d.). Etymology of Louise. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/Louise