The Nuremberg Trials held Japanese war criminals accountable for crimes agenst humanity in violation of the rules of war true or false?

The first Nuremberg trial were only for the European war criminals (Class-A). Subsequent Nuremberg trials were held for lesser criminals. Other European countries also held separate trials for lesser war criminals (Class B & C).

The International Military Tribunal for the Far Ear were for major Japanese war criminals (Class-A). Other countries held separate trials for lesser (Class-B and C) war criminals.

Also after WWI Germany agreed to hold war crimes trials but since the allies did not occupy the German/Austrian nations, the trials were not generally successful, thought the court did its best.