You may also choose to join the Axis if world tension is high enough, and if you have enough fascist support in your country. Exceptions: Japan (If non-aligned or if created Greater East Asian Co-Prosperity Sphere) and Nationalist Spain (before 1941-42). You may choose to join the Axis as any fascist country by utilizing the 'Ask to join faction' button. In the base game, Italy and Japan have focus tree events that will allow you to join the Axis. In Hearts of Iron IV, there are many ways of joining the Axis. However, Germany can easily add members such as Italy, Hungary, and Romania to their faction. Its only member at the start of the game is Germany.