basically, it was (and is) more or less same around Europe. I used a document from 1927 as reference to Soviet traffic code. I didn't find proper documents on American ones, or any other traffic code yet. There will be new sets for different countries, though. If there will be any luck in finding a proper document with detailed traffic signs description

https://upload.wikimedia.org/wikipedia/commons/thumb/7/71/Finland_road_sign_C38.svg/800px-Finland_road_sign_C38.svg.png

umm, these are still very much in use.