the First War of the Planets began in 1900 when Selenite Cown Prince Tarkor was assassinated During a visit to the Jovian Independent moon of Io by anti Selenite Rebels. the Lunar Government blamed the Ionian government for the assassination and sent an ultimatum to Io that would result in war being declared.
However, this conflict would quickly spiral out of control. a few decades before, the planet Earth was united under the British Empire, creating the Terran Empire. Over time, the Terran Empire managed to become a Solar Power, using advanced steam powered and Diesel Powered technology. However, this would bring the Terran Empire into conflict with the Martian Empire. the Martians used similar Technology to the Humans, but the Humans had evolved technologically much faster than anticipated, making the Martians try and catch up, specifically using the all-powerful Martian Star Fleet. When the Terran Empire began to send men into space, the Humans quickly made contact with the Ancient Selenite Empire on the Moon. Because of the close porximity, the Terran Empire initially tried to counquer and colonize the Moon, but decided to form an alliance instead, which resulted in the Humans siding with the Selenites in the upcoming conflict. However, The Plutonian Empire also came to the defense of Io and began to mobilize. The Plutonian Empire was a Crumbling Autocracy that was far behind the rest of the Solar System in the Diesel race. Despite this (as well as the Planet's small size) Pluto had a large empire (mainly in the Asteroid belt), however, Pluto had also lost the Great Game with the Martians, resulting in the Empire going into even more decay. the Sate of Venus also began to mobilize, knowing that the Humans would likely target them as well. Unlike the Other Solar Empires, the Venusians were Technocrats, who were run by the most intelligent in their community, and they were also enemies of the Humans due to a war with the Humans during the Human Unification War. The fear was corrected as the Terran Empire launched an invasion of Venus, but the invasion was launched by attacking Martian Allies in the Area, Bringing Mars into the War on Venus's side. Overtime, Neptune would join the war against the Human Formed Alliance, while the Kingdom of Ceres would join the war against the Alliance (despite being a former member of said alliance, the Empire of Triton would also join the Alliance after heavy consideration.
Overtime, fighting Expanded beyond the Solar System, in the Proxima Centauri System, the Planet Aurela went to war on behalf of the Martian and Venusian dominated Federation, where they attacked Terran Colonies in the System. Back in the Solar System, Uranus waged war against Neptune and Triton, However, the largest front was the Terran Venusian Front, Mars and Venus had both attempted to launch invasions of Earth and Trench Warfare had popped up in the formerly peaceful Venusian Tropics, New inventions were being deployed to break the stalemate. For Example, the Martians had to modify their formerly powerful Tripods to be smaller and faster, and even creating floating "Mantapods" (from the 1953 War of the Worlds movie). The Plutonian Military was focusing most of its military might against the Terran Colonies in the Asteroid Belt, but the Plutonians were ill-prepared for war, and after the failed invasion of Earth by the Plutonians, the Emperor has been focusing on holding their Asteroid Colonies.
The Stalemate would eventually break in 1903 when the Plutonian Revolution began. the revolution overthrew the Imperial Government and was led by Soldier returning from the front. After the Emperor was thrown out, the "Salvationist" party would take over, an Anti-War Party, but not before a bloody civil war between the Salvationist Army and the "Grey Faction" consisting of people who did not agree with the new order. The Salvationists would win the war and call for peace with the Alliance, but this resulted in the loss of many of its asteroid colonies.
With the Fall of Pluto, the Terran Empire thought they would achieve victory, but this would not be. in 1903, the Terran empire sent a Space Telegram to the Moon of Cronera, promising them greater influence if they joined the war on their side in the case that the Cronerans joined the war against the Federation. Not Only did they refuse, but the space telegram was intercepted by the Martians, and when Cronera found out, they declared war. Cronera is a planet in the Pleiades System that was formerly a Martian Colony which gained independence and quickly became an economic powerhouse. The massive amount of Croneran troops began to push back the Terran Troops until the Terran Empire Called for Peace. this would result in the Treaty of Venus. the Treaty would replace the Terran Imperial Government with a Technocratic Government, Disband the Selenite Empire (not blow up the moon) and the Neptunian Empire.
the 1910s were a time of great celebration. Cronera had a massive economic boost that became known as the "Roaring Tens," However, the Cronerans would also try to stay out of galactic affairs and spend its time doing its own thing. Meanwhile, Mars and Venus had become the dominant Solar powers, making several Colonies throughout the milky way. Although Venus still lost a majority of its fighting age men on the Front, Resulting in Mars becoming more Powerful.
the 1920s were not as good as the 1910s. the Croneran Stock Market crashed resulting in Cronera, Mars, and many other planets going through a "Great Depression." This would also become a time of Nationalism. During the War, Ceres conquered most of the Asteroid Belt, However, they wanted more, and now a Nationalist Government has taken over and is now promising to bring Hegemony to the Asteroids. Back in Aurela, the Hypernationalist Military also wanted more from the War and had invaded its neighbor of Tau Ceti. Despite this, the the Solar League has done little to stop this. the Plutonians are now a Totalitarian Pariah State.
However, the most worry-some event is the Rise of the Terran Nationalist Party on Earth. the TERNAT party has taken power in the Republic using Human Supremacist Propaganda and promising to create an "Eternal Empire". Already, the Empire has been persecuting Non-Humans and the leaders of the Empire also have made plans to destroy what they believe to be the Biggest threat to Earth and the Human Race...