Where did Cinderella take place?
France. In the 19th century, the Grimm Brothers of Germany started a movement to record local stories of local people. They recorded the stories of Germany. Other people wrote the stories of other people. Many different versions of the Cinderella surfaced. We use the French one. While no one particular event occurred just like the story, it does happen that kind and beautiful servant girls do marry princes. Tales like Cinderella contain some truth.
I think the producers of this film left it ambiguous intentionally. Although the first thought goes to France (with the names, aesthetics), there are other clues as well. When Cinderella flees the castle, both mademoiselle and senorita are called out after her. Through careful consideration I have come to the assumption that it would most likely take place in Belgium.