My first thought was French too, but that looooong wheelbase for that era seems out of place!

I restored a French racer for my buddy (it's his bar bike) and the wheelbase and angles are from that era when they hit the limits on wheelbase and angles. I think maybe a Rigi might be tighter in the rear. It's the squirrelyest (word?) bike I have ever ridden. Too much fun.

What looks so French to me is the lugs.