A point of history that might be interesting is that Aikido was founded @ circa 1942. Post war Japan was very limited to Martial Arts practice and most ryu were banned, dissolved, or they retreated into secret practice. So what do you do to keep your martial art (distilled from ancient Daitoryu) from being banned?
""Oh, this? Uh, it's
"The Way of Peace and Harmony" let us demonstrate."" ""Well, that doesn't sound too threatening, does it? It can't be too dangerous with a name like that, you may continue your practice, if you show us how to do it.""
The name "Aikido" was adopted to conform to the pre-war Dai Nihon Butokukai guidelines - 1942 was well before the war ended.
In any case there was never a general ban on martial arts post-war Japan, that's a common misconception. There was a prohibition against martial arts training as part of school curriculum, that's all. Of course, a lot of people were too busy looking for food to think about training in the years immediately following the war.