A relatively young Gungan, Jar Jar was banished sometime before the Battle of Naboo for causing numerous accidents, such as crashing the Bosses' "heyblibber," flooding Boss Nass's mansion, and opening half of the bubble cages in the Otoh Gungan Zoo. Viewed as a danger to other Gungans, he was sent into the swamps to fend for himself. Although he subsisted on a meager diet, including raw shelfish and tree-dwelling gumbols, Jar Jar managed to survive alone until the arrival of the Trade Federation.
After he was resucued from Trade Federation Forces by Qui-Gon Jinn, Jar Jar swore a life-debt to the Jedi Master, as is required by his culture. He then led Obi-Wan Kenobi and Qui-Gon Jinn to the relative safety of Otoh Gunga, despite the knowledge that he would be punished upon his return. When Qui-Gon learned that Jar Jar would be punished for breaking the "noncombackie law," he used the Force to convince Boss Nass to release Jar Jar.
After numerous adventures, Jar Jar found himself back on Naboo with the Queen and her entourage in tow. At the Queen's request, Jar Jar led them to the Gungan Sacred Place, where the Gungans had retreated after a Trade Federation attack on Otoh Gunga. Boss Nass and Queen Amidala became allies and, for his part in bringing the two species together, Jar Jar was made a general in the Gungan Grand Army.
As a newly-appointed general, Jar Jar led a contingent of militagungs at the Battle of Naboo. Although he did not prove more composed, he did manage to avoid being injured or killed. And, while his clumsiness still caused several accidents, these mishaps all proved to the Gungans' advantage. He was briefly captured, but the battle drods surrounding the Gungans were deactivated when Anakin Skywalker destroyed the droid control ship.