Without the Fall of France and Vichy how long could the Third Republic hold on without reform?
How would the French Political Parties Fair?
French Third Republic was established in 1871 and last until 1940 so 69 years, and it took a cataclysmic defeat and the establishment of a dictature to bring the regime down. So it could live forever.
In the late thirties, you have severals people who have plans to reform the regime and they put these plans into action in 1945. So without a war, these plans could be put into action a little earlier or a little after than OTL. It will stay a parliamentary regime as is 3/4 of Europe today.
I suppose it depends on why there's no WW2. The existence of Nazi Germany pretty much guarantees an alt-WW2 of some kind, and a lack of Nazi Germany will affect the path of France throughout the 1930s.
Should we presume the usual plausible no-Nazis scenario—conservative nationalist monarchists à la Schleicher, Papen and Hindenburg take power as an authoritarian but non-insane dictatorship? Or are we going for the (rather harder to achieve) Weimar-survives route? Or do you mean for there to be a Nazi Germany that later gets overthrown by a military coup d'état? (I discount KPD Germany, which is just not going to happen, full stop.) These things will affect France; for instance, Action Française will be affected if their ideological brethren (monarchist, anti-Semitic, conservative, traditional, strongly religious, anti-democratic) take power in Germany, though not necessarily strengthened (I daresay that the French wouldn't want to go along a route that can be painted as too German).
The scenario I'm working with has a coup of Hitler and the Nazis in 1939 which degenerates into a short civil war from around 1939-1940.
The Soviets take over some of the baltic states in the chaos but Poland survives. So politically its like all the OTL road to war happened but their was an anti climax in the 1939-period after the Alt Munich.
The new mostly democratic Germany
The scenario I'm working with has a coup of Hitler and the Nazis in 1939 which degenerates into a short civil war from around 1939-1940. The Soviets take over some of the baltic states in the chaos but Poland survives. So politically its like all the OTL road to war happened but their was an anti climax in the 1939-period after the Alt Munich. The new mostly democratic Germany, Is really only lightly damaged still has Austria and parts of the Sudetenland so by 1949 there they are going to the pivot on which Europe turns again much earlier then they were in OTL.
In conclusion France isn't invaded but Germany will still be much stronger than it. So all in all a mixed bag.