The Martian Empire, later known as the Robotnik Empire, is the most powerful political and military authority on the planet Mars in the Sol Alliance. It was founded in 2089 C.E. when Mars was first settled by colonists from Earth. Mars was quickly declared a completely separate and sovereign world, independent of Earth. Despite rigorous terraforming processes, Mars remains a harsh and rugged world, which the human populations on the planet have been forced to adapt to.
In recent times, the Martian Empire has been led by Emperor Ivo Robotnik, who has kept Mars in a hostile standing with Earth and its leaders. It is also notorious for its actions in the realm of Mobius, where they launched a campaign of conquest known as the Freedom War. Emperor Robotnik also decided to rename the Martian Empire in tribute to himself.
The Martian Empire has been in tension with Earth for decades, but only invaded its neighbor once, without ultimate success. This was during the War of Deceit, where, under the direction of the Skeleton King, they performed a massive attack that resulted in the destruction of the White House and the Capitol Building in the United States. Not long after, the surface of Mars was incinerated by Sol's supernova caused by the Andromeda Treaty.
After the war's conclusion, where all the effects of the war were removed, Mars remained the mechanical dynamo it always has been. Since then, The Robotnik Empire has been quiet and not very active in Atmah. In Mobius, however, it still continues its campaign of conquest.