yes, TinTin and Spirou are Belgium and they began before 1940.
but they became world fame in 1960s in same time the French comic made similar evolution
there is gap in Belgium comic, while Walloon team up with french to form the French-Belgium comic world
Went the Flemish another way independent with connection to Netherlands
like Will Vandersteen with Spike and Suzy ( US tittle: Willy and Wanda ) or ingenious Nero by Marc Sleen.
French-Belgium comic world flourished with work of Herge The Adventures of Tintin, Peyo the Smurfs, Jacobs Blake and Mortimer, André Franquin version of Spirou and his mean Gaston and Morris Lucky Luke or the devil of a fellow artist Jijé
but that work was split under two publishing house: Lombard (Studio Herge, ligne Clair style) with magazine Tintin and Dupuis ( Marcinelle School style) and there magazine Spirou
in same time allot of French artist and writers were looking for Jobs in Belgium Comic like Albert Uderzo, René Goscinny they work for little while for Spirou in 1950s
Also allot of French and Belgium comic artist made educational tour to USA ! like Jijé who took Morris, Franquin and Will on lunacy odyssey true 1950s USA
At end of 1950s Albert Uderzo, René Goscinny left Dupuis with disillusion about creative freedom, back in France Goscinny proposed publishing house Dargaud, a Comic magazine in stile of Spriou,
It Became PILOTE the first issue feature a story by Albert Uderzo, René Goscinny: Asterix, the Gaulle
Allot of Belgium and French Artis came to PILOTE to work because editor René Goscinny guarantee Artistic freedom, what Catholic conservative Lombard and Dupuis not offer in that time.
a new Generation of Artis came and join the team of PILOTE, Like Jean-Claude Forest Babarella, Jean Giraud Blueberry and returning from educational tour to USA Jean-Claude Mézières Valérian and Laureline
now during 1960s the French-Belgium comic world explode, but instead to stop, it went in higher gear
a exhausted Jean Giraud went to trip in Mexican desert, after some months He return calling himself now Mœbius
Mœbius and other french artis start there publishing house: Les Humanoïdes Associés (the united Humanoids) and there legendary magazine Metal Hurlant (US tittle: HEAVY METAL)
Now how to give this a way into USA and it Comic Superheros market ?
one way would be the Bankrupcy of Marvel or DC Comic (what happen several times almost)
other way is that US Congress push harsher Comic code, like Batman & Robin is banned for calumniation about it's Homosexuality tune
that publishing house editor are force switch to French-Belgium comic imports like The Adventures of Tintin, Spirou and the Smurfs
until they are reorganized, only to realized that readers really like those comic more that superheros...