Background: Darth Sidious, also known as Sheev Palpatine, was a Force-sensitive Human male who served as the Supreme Chancellor of the Galactic Republic during the Clone Wars. A Dark Lord of the Sith in the Order of the Sith Lords, recorded by history as the most successful who had ever lived, his deeds resulted in destabilisation of the ancient Republic and the noble Jedi Order from within. Noted for his sadistic and self-serving intentions just as well as his ability to conceal them, Palpatine impacted the galaxy perhaps more than any other single individual, and it is likely that his impact on history, for good or ill, was immeasurable.
Born in 82 BBY on the planet Naboo to the aristocratic House Palpatine, Palpatine discovered the Sith at a young age as a collector of dark side artifacts. In 65 BBY, he met Hego Damask, a Muun businessman who was in reality the Sith Lord Darth Plagueis. Under Plagueis's manipulation, Palpatine killed his father and pledged himself to his new Master's dark side teachings as Darth Sidious. Palpatine lived a double life for many years, serving an untarnished career as Naboo's ambassador in the Galactic Senate while learning from his master and training a young Zabrak as the Sith assassin Darth Maul. Plagueis and Sidious, both exceptionally skilled and powerful in the Force, were able to conceal their identities from the Jedi for decades. As Plagueis privately searched for the key to eternal life, Sidious manipulated galactic politics, culminating in the blockade of Naboo by the Trade Federation. In the wake of the political crisis, the Galactic Senate voted to elect him as Supreme Chancellor, and around the same time, in accordance with Bane's Rule of Two, Sidious murdered Plagueis and usurped the role of Sith Master.
As Chancellor of the Republic and Dark Lord of the Sith, Palpatine orchestrated the outbreak of the devastating Clone Wars ten years after the Naboo Crisis. He himself headed both the Galactic Republic and, secretly, the Confederacy of Independent Systems. The public leader of this splinter faction was former Jedi Master Count Dooku, Sidious's second apprentice as Darth Tyranus in the wake of Maul's presumed death on Naboo. With the assistance of Darth Jar Jar, he was able to get the Senate to give him emergency powers.
Palpatine, in the wake of his plans being compromised in the wake of the portals, temporarily left the Senate for two months under the pretence of illness, while getting Darth Jar Jar to make sure he did not lose his seat of office. During his trip of discovering the source of the portals, Sheev would end up back on Naboo as the source of the disturbance. Finding a dark side Nexus under his old estate, he was able to use it to gain complete control of the portals, being able to manipulate space-time to a massive degree while acquiring great knowledge of the galaxy. He would later be led to Mortis using the knowledge from the Nexus, where he would trick the Mortis Gods into subduing themselves into submission.
Returning back to the Republic, Sidious would be enraged to find out the Jedi were discovering the Byss Lane and that pro-Jedi sentiment was higher than ever, undoing years of his work. He would induct Mandalore into his plans to subvert the Jedi's new reputation.
With the re-emergence of the Sith Empire, Palpatine sensed his apprentice's desire to join the group and finally overthrow his Master. Sidious, acting before Tyrannus could, wiped his and Jar Jar's minds of all details of the Sith Grand Plan. This setback would not stop Sidious, as he immediately formulated new plans to use the Sith Empire to his advantage.