Another fun one, thank you! Just one little thing, (sorry, bachelor's in history), Sieur means "lord" or "sir", and LA SALLE means "the hall" or "the manor". Turns out Rene-Robert Cavelier actually bought the title "lord of the manor" aka "Sieur de La Salle". His last name was Cavelier. Wikipedia has an interesting entry on the title and how it's become known essentially as his last name - under Early Life and before Expeditions:
https://en.wikipedia.org/wiki/Ren%C3%A9-Robert_Cavelier,_Sieur_de_La_Salle
This is interesting as always! I always get stuck on the appropriate way to reference English nobility as well… but I will bet dollars to donuts (*) that very, very few of my fellow Chicagoans know that "LASALLE" isn't his last name! What would be a more accurate way to clue this?
(*) This saying surely made more sense way back when in the time that donuts cost way less than a dollar…
It's way too long but what about something like "Title of French Mississippi explorer Rene-Robert Cavelier that now shows on Chicago's financial artery and is also the name of the southern-most borough of Montreal, Quebec"? Or, since everyone just assumes that's his last name anyway, just leave it.