DUBUQUE (spelling) Several spellings of "Dubuque" have occurred. Julien DUBUQUE wrote his name as we know it today, "Dubuque." In the published records of the commissioners who adjusted Spanish claims within the LOUISIANA PURCHASE, there is one instance of the name being written "Dubuc" and several occurrences of "Dubugue." These errors have generally been blamed on a copyist or proofreader.
The name has also been written Du Buque. People writing the name in this manner believed the "du" meant "of' in French. The prefix "du" is not, however, capitalized if used in this way, and the word "Dubuque" as a French name would be spelled "Debuc" without the use of the capital "B."