In which nation did a nationalist military regime lead the country to invade its neighbors and launch world war ii?

The correct answer would be Germany.

Under the control of Adolph Hitler, Germany would invade numerous countries throughout Europe. This includes France, Poland, Great Britain, etc. Along with this, Germany broke a prior agreement with the Soviet Union and invaded them as well. This was one of the most significant causes of World War II, as Hitler refused to abide by the agreement set up by him and other world leaders at Munich.

well, there are a lot of places we get information about earth from. like science classes, websites, books, newspapers, etc.