Before she appeared in the Mandoverse, a.k.a the TV shows and movies connected to and set during the same time period as The Mandalorian, the last time we saw Ahsoka was in the epilogue of the Rebels series finale. While most of Rebels is set during the five years before the Battle of Yavin (BBY), the epilogue is set approximately in 5 ABY, or a year after Return of the Jedi. In the epilogue, Sabine and Ahsoka set off to find Ezra Bridger, a young Jedi and Rebel who disappeared with Imperial leader Grand Admiral Thrawn during the Liberation of Lothal in 1 BBY.

There will likely be some flashbacks to the Clone Wars era in Ahsoka since Hayden Christensen is reportedly set to return as Anakin Skywalker, but the main story of the show will take place roughly 10-11 years after Ezra’s disappearance and 5-6 years after the Rebels epilogue. As with The Mandalorian and The Book of Boba Fett, the Empire has been officially defeated at this point in the timeline and the New Republic has taken control of the Galaxy’s government. 

But even though the Rebels won the war, there are still some Imperial officers and sympathizers trying to regain power. With Moff Gideon’s death in The Mandalorian season 3, the surviving loyalists are likely looking to fill the power vacuum left in his absence. Based on the Shadow Council meeting we witnessed before Gideon’s death, there are still some who believe Thrawn is the true heir to the Empire and that his return could help them regain control of the Galaxy. While Ahsoka will likely show us Thrawn’s role in the New Republic era and how his return could give the latent Empire forces more power, that doesn’t mean we have to worry about the rise of the totalitarian First Order just yet, as the series is set about 25 years before the Sequel Trilogy.

Even though the Mandoverse’s timeline includes many intersecting shows, it’s safe to say that we can expect the majority of Ahsoka to take place around 9-10 ABY, or 5 years after Return of the Jedi.