Modern day Brabant, Belgium changed from the Julian calendar to the Gregorian calendar on December 14, 1582 (at the time Brabant was a part of the Netherlands). The Gregorian calendar was temporarily suspended in favor of the French Republican calendar from September 22, 1792 until January 1, 1806.
On a visit to the genealogy reading room at the National State Archives of Belgium, I first encountered the French Republican Calendar. The person next to me was kind enough to help me and gave me a copy of his "translation" to our present day calendar. I am preparing a file which can be printed. COMING SOON
For more information on calendars, here is a collection of sites: