Allow me to elaborate, we can assume that Mario hated Mussolini and his fascist regime in general as we can see in the game Super Mario Kart 2 that he has a particular distaste towards the political right, therefore we can pinpoint that Mario and his friend Luigi (who is a hardline communist according to Super Mario) had joined an anti-fascist resistance group (possibly the National Liberation Commitee) and participated in sabotaging Italian supply lines, therefore delaying the Italian war machine, he might also have collaborated with the Allied Powers when they were invading Italy, defeating the German-aligned Italian Social Republic and witnessing Mussolini’s execution. However, he might not have stopped there, he might have helped the Allies push into Germany and then capture Berlin. Now on to Wario, which unlike the latter two, sided with the Axis Powers and enlisted into the German Waffen SS and a top member at that, being one of Hitler’s closer allies. He mainly participated in the invasion of Poland, which just like other SS members, participated in the mass persecution of Jews. After that, he also participated in the first half Operation Barbarossa, in which he had his leg blown off by a Soviet landmine in 1942, he then retired from the SS to live a simple life in Saarbrücken. Only 3 years later however, his country had already surrendered to the Allies, and his city was now under French occupation, with the help of his remaining friends in the former Wehrmacht, fled to Argentina to live another 50 years of his life with a fake identity in Buenos Aires, but was found and captured by Israeli Mossad agents and put on trial. Now back to Luigi and Mario, it was now the time of the Cold War, this also when Mario and Luigi’s relationship start to deteriorate, Mario was pro-democracy and aligned with NATO, while Luigi (as mentioned earlier) is a radical socialist and had defected to the Warsaw Pact, now living in the city of Kaliningrad, Russia. However that’s a story for another time, after all, its just a theory, a Game Theory.