I know there are questions about Jar Jar’s age and relevance in the films already, but I was under the impression that when all the Jedi were killed between 3 and 4 that he had been murdered as well. Am I wrong? Or do we not know?
In what was previously considered "C-Canon" (now "Legends"), Jar-Jar survived until at least 6.5 ABY.
He made an appearance in an expansion of the Star Wars: Galactic Battlegrounds game.
Binks was alive and well in 6.5 ABY, and was present on Coruscant during its liberation from the Galactic Empire by troops of the New Republic. While he was never involved in this liberation, he was situated relatively close to some of the action.
Regarding whether or not not he can/will appear in Episodes 7-9...
The guidebook Ultimate Alien Anthology specifies that Gungans live an average of 65 standard galactic years.
According to Star Wars: Episode 1 Insider's Guide, Jar Jar was born in the year 52 BBY.
Statistically speaking, that leaves 9 years for Jar Jar to live (The Battle of Endor occurred in 4 ABY). Since rumors state that the new trilogy will take place 20+ years after the Battle of Endor, it is unlikely that Jar Jar will have survived until the timeframe of the new movies.
With the recent Canon Purge, however, it is unknown what his current fate is, or what the average lifespan of a Gungan is.
In Disney Canon, Jar-Jar survives until at least the timeframe between Return of the Jedi and The Force Awakens.
Jar Jar appears in the new Book Star Wars Aftermath: Empire's End.
The conclusion of a trilogy, mostly set between Return of the Jedi and The Force Awakens, Empire's End contains plenty of rewards for long-term fans. One of these is an interlude set on the planet of Naboo. A refugee boy named Mapo encounters a Gungan performing for kids on the streets, clowning around in a fountain twice a day while being studiously avoided by the grown-ups.
"Meesa Jar Jar," says the clown when Mapo introduces himself. The clown distracts the orphan from his own sadness by popping his eyes and bulging his cheeks, but is hiding a sadness of his own.
"Jar Jar makin some uh-oh mistakens," the Gungan says, explaining why he isn't wanted anywhere either. "Desa hisen Naboo tink I help the uh-oh Empire." He stares into the distance, suggesting he knows more than he's saying.
According to Star Wars: Droid Tales, the last we see of Jar Jar is he is floating in space past the Death Star II (see 2:52 in the below video):
I think that Jar Jar would have survived for two reasons:
- One - because killing Jar Jar would result in a huge argument in the senate because people like Jar Jar - from the people of alderaan to the people of naboo -
- Two - also it is rumored in the 6th movie, near the end, that Jar Jar says "Mesa is alive". I for one have no proof of this but it is a possibility; though you would have to listen to the audio to see if it is true.