Jupiter was the third of King Walter Good's sons, but was chosen by his father over his two elder brothers to succeed Walter as king. This left Jupiter's oldest brother Bleston bitter and resentful, and he plotted against Jupiter for a time before departing First Warren with several followers. To confirm Jupiter's status as the heir, King Good held a ceremony at which the Green Ember was removed from the Crown of Flames and presented to Jupiter. Jupiter held this down payment of his inheritance for five years until his father's death, at which point he ascended to the throne.
After many military victories, such as his defeating the wicked wolf king Garlacks in the Red Valley War, King Jupiter turned to diplomacy to expand peace. Through that and military might he was able to become sovereign of the Great Wood and banish the Birds of Prey back to the High Bleaks. He also formed the Council of Seven Ambassadors to assist in his diplomatic efforts. Their chief was Garten Longtreader, who was credited for much of the expansion of King Jupiter's realm. This eventually saw the birth of the Great Alliance, which not only included once rival rabbit warrens but also squirrels, small birds, and other creatures.
Unfortunately, Garten turned against his king and cause, and betrayed Jupiter into the clutches of Morbin Blackhawk and Redeye Garlackson, the son of Jupiter's old enemy Garlacks. With his armies deceived and Wilfred Longtreader, his only companion at the time, lured away and captured, Jupiter was easy prey for his enemies. It is thought that Morbin hoped to hold Jupiter as a hostage and use him, but Jupiter spoke out defiantly against his foe. As a result, Morbin killed him in a rage, but Jupiter had already prepared for the future by passing the Green Ember on to his chosen heir and youngest son Smalden Joveson.
The site of Jupiter's death afterwards became known as Jupiter's Crossing, a tragic yet holy site for many of the rabbits of Natalia. Jupiter's memory and dream were honored by many, who came together to form The Resistance. Jupiter's great deeds and story were immortalized in both The Rise and Fall of King Jupiter the Great and in the windows of Cloud Mountain's Lighthall. The thirteenth anniversary of his death became a cause for celebration, as Smalden was saved from a similar fate to Jupiter's by the actions of Picket Longtreader.
It was later revealed that Jupiter and his wife, Lady Glen, had-in addition to ten sons and an unspecified number of daughters-a daughter newly born at the time of Jupiter's death: Emma. Additionally, though Jupiter held the Green Ember and wore the Crown of Flames during his reign, the Whitson Stone that he should also have held came into the possession of his brother Bleston.
The anniversary of Jupiter's death came to be commemorated among the Lords of Prey and the rabbits subservient to them as Victory Day. This took on a new meaning when led by Emma, the Cause won the Battle for First Warren on that day. In the process they deposed the city's governor, Jupiter's eldest son Winslow, who had dishonored his father's memory by siding with his murderers.
Jupiter was known to be a tall, brown-furred rabbit.
Personality and traits
King Jupiter was like his father King Walter, but more jolly and wise. Though he was for a time proud of his abilities as a fighter, his constant participation in conflict came to trouble him. In humility he sought instead to find peaceful solutions to problems. This enabled him to not only resolve generations old rivalries between different rabbit settlements, but also to form alliances with other creatures that had previously been though impossible.
Jupiter's greatest accomplishment, in his own opinion, was "That [he] was his father's true son." Even in his darkest moments, held captive by Morbin Blackhawk, Redeye Garlackson, Garten Longtreader, and their forces, Jupiter remained hopeful. When Morbin threatened to burn the Great Wood, Jupiter prophesied the Mending and a golden age more glorious than anything even he had accomplished.
Jupiter's fighting skills were legendary, as demonstrated by his stunning defeat of Garlacks in single combat. He was also a great military leader, such that Wilfred Longtreader believed that had he lived the rabbits would have been certain to win a war against the Lords of Prey.