The Kir is named after the Catholic priest Félix Kir, a Nazi resistance fighter in the Dijon region during WWII. Félix Kir is credited with helping around 5,000 POW escape during the course of the war. After the war ended he was elected mayor of Dijon, where he stayed for 23 years till his death in 1968.
Felix combined the two regional beverages of Creme de Cassis and a dry acidic white wine made from the Aligoté grape to create the Kir. I think the proportions I have provided are spot on but the goal of adding the Creme de Cassis is just to take the dry acid edge off the wine. You’re looking to make a white wine with a mild currant flavor and not a super sweet cocktail. I recommend using as dry a wine as possible because the creme de cassis is already really sweet and if you start off with a sweet wine then it’s just a bit too much and you lose the other flavors. The dryer the wine the better.