In November 1830, the Belgian National Congress declared
independence from the Netherlands, and had drawn up a constitution.
Now in resistance to this secession, Dutch troops invade Belgium.
However, they are forced to withdraw two weeks later, on 20th
August, when the French army enters Belgian territory.
Citation:
Editors. "Dutch troops invade Belgium".
The Literary Encyclopedia. First published 30 December 2011
[http://www.litencyc.com/php/stopics.php?rec=true&UID=17952, accessed 20 May 2013.]