Did they have anime in Belgium in 1956?

Well, a simple Google search yields a result that pretty clearly says no. According to this site, which may or may not be accurate:

http://en.wikipedia.org/wiki/History_of_anime

The genre was developed during the first half of the 20th century, but given the insular nature of Japanese society, it's pretty unlikely that Japan would export anything to anywhere that didn't already have a significant Japanese population. Belgium wouldn't qualify on that score.

In addition, the site identifies the first significant separation from western animation as being in 1970, with further development in 1980, so...again...it seems pretty likely the answer is No. Hakujaden wasn't released until 1958, and that would likely be the first film that might have been translated and shown outside of Asia.

Given that NaNo is now over, and far fewer people will be visiting the forums it is all the more likely you won't get answers to questions such as this and Google becomes even more significant, even if the search takes no more than a minute or two.