Belgian literature comes in two flavours: that written in French and that written in Dutch.
Because there are more powerful countries on either side that speak these two languages, Flemish and Wallonian literature are not as well known in Britain as they might be. But consider this: there are Flemish authors writing in Dutch in Ghent, Aalst, Brussels, Antwerp, Bruges, and so on, which are cities that are, as the crow flies, nearer to London than Edinburgh or Glasgow! While Brits know "everything" about Irvine Welsh, Lewis Grassic Gibbon, Muriel Spark, Neil M. Gunn, Alasdair Gray, Liz Heron, Ian Rankin, and a host of other names from Scotland, they know virtually nothing about what the Flemings wrote in French, and write in Dutch.
If you asked, say, 2,000 people on the streets of central London, only a dozen (apart from Belgian, French and Dutch tourists) would be able to name one Belgian author, let alone actually having read one. And nine of those would be clever-dicks who had realised that Simenon was Belgian, not French.
In the nineteenth century, when the language of education in Belgium was French, there were quite a few Flemish authors who spoke a dialect of Dutch at home, but would write in the language of elegance and education, French. Authors like Maeterlinck, Verhaeren, Ghelderode and a host of more minor authors were French-writing Flemings.
Scroll forward to 2008. Nowadays the Belgian literary communities are more neatly divided into Dutch and French-writing authors. The tragedy is that authors writing in both French and Dutch in Belgium are almost always published abroad, i.e. in France or the Netherlands. The Belgian publishing industry is not strong - and yet some of the most innovative authors are Belgian. So Nothomb, Harpman and Toussaint are recognised as Paris authors, and Boon and Timmermans would never have become as famous as they are (in the Low Countries, as they are virtually unknown in Blighty) if they hadn't published in the Netherlands.
I hope to be able to write things about Belgian authors on this forum, but I cannot deny that interest will soon pall on the World Literature Forum, unless those that cannot read Dutch or French find a few translations available.
There are a few English translations doing the rounds (Google for more information). Louis Paul Boon and Ivo Michiels have both had novels of theirs published in English translation. The recently deceased Hugo Claus also has his major novel "The Sorrow of Belgium" in English translation. Nothomb I have dealt with elsewhere. But there are quite a considerable number of contemporary Flemish and Wallonian authors that will be entirely unknown in Britain. I hope I can introduce people to a few, over time.
One final point about language usage. The culture, history and geography are Flemish or Wallonian, the language is Dutch or French. Except in one case: those writing in a very strong dialect of French, or language in its own right, depending on taste, do write in Wallonian. But most Flemish authors do not write in dialect, they write in standard Dutch, with some regional vocabulary input.