In Star Wars: The Empire Strikes Back, fans were first introduced to Yoda, a Jedi Master who, despite his small stature, was one of the greatest Force wielders in the galaxy. Luke Skywalker first met Yoda on the swamp planet Dagobah, a place void of any type of civilization and filled with muddy waters, vines and reptile-like creatures. Fans came to understand that he was in exile on Dagobah, hiding from the Empire after Palpatine executed an order to kill all Jedi throughout the galaxy. However, it turns out Yoda wasn't on this planet by accident.
In Star Wars: The Clone Wars, it was revealed that, shortly before the fall of the Jedi, Yoda made a trip to Dagobah -- and it's because of this visit that he would seek refuge on this planet when the Jedi became hunted.
Season 6 of The Clone Wars ended with a story arc that focused solely on Yoda and the larger workings of the Force. It all began when the Jedi Master began hearing the voice of a Qui-Gon Jinn, who was killed by Darth Maul in The Phantom Menace. Since Qui-Gon was the first Jedi to ever exhibit consciousness after death, the rest of the Order couldn't be certain this wasn't some sort of trick concocted by the Sith. However, Yoda remained true in his belief, and he followed Qui-Gon's instructions.
In order for them to better communicate through the Force, Qui-Gon told Yoda to travel to the planet Dagobah. Taking a small fighter (and R2-D2 along with him), Yoda first traveled to the swamp planet. There, the Jedi Master instantly noticed the planet's strong connection with the Force, which Qui-Gon described as one of the purest places in the entire galaxy. On this first visit to Dagobah, Yoda learned more about the Cosmic Force and Living Force, and how one feeds into the other. Qui-Gon even led his old master to the same cave Luke would enter years later where he saw a vision of the terrible future that would soon befall the Jedi.
Yoda's first visit to Dagobah was brief, but it was enough for him to recognize the planet's powerful connection to the Force. It makes sense that, when he found himself in need of a hiding place, he would go there to not just to continue his training and learn more about the Force, but also to guide and train the galaxy's savior decades later. It's also because of Yoda's initial visit to Dagobah that he would eventually learn to live on past his physical body, a powerful skill that would allow him to return as a Force Ghost in Return of the Jedi and The Last Jedi.
Streaming on Disney+, the final season of Star Wars: The Clone Wars stars Matt Lanter as Anakin Skywalker, Ashley Eckstein as Ahsoka Tano, Dee Bradley Baker as Captain Rex and the clone troopers, James Arnold Taylor as Obi-Wan Kenobi, Katee Sackhoff as Bo-Katan and Sam Witwer as Maul.