No 1st or 2nd World Wars would really help. If you manage to divert the national rivalries of the still strong Great Powers into a multinational space race then you could see substantial acceleration of research.
The A9 Amerika Bombaer would have techinically been a spaceflight even if it was a suicide mission. Maybe if the A9 was fastr in coming into service and the war in Europe lasts a few months later you could hav a German in space by 1945 or 6.