In an alternate timeline where Edith Keeler did not die in an automobile mishap, the Interstellar Axis was an interstellar organization of states founded by the Nazi leadership of the planet Earth's Erdenreich in collaboration with Qo'noS, Axanar and Romulus. (Last Unicorn RPG module: All Our Yesterdays: The Time Travel Sourcebook)
History and specifics
In the 21st century, a Nazi interstellar empire blossomed when sleeper ships of the Raumwaffe overran Alpha Centauri, assimilated their technology to develop warp drive, and began conquering neighboring systems Tau Ceti and Capella. In 2084, Andorians resisted advancing forces, and although Andoria was captured, significant numbers of exiled refugees were able to form a resistance movement on Cimera III with Vulcan aid that grew to become the Alliance of Free Planets.