The Tann Province, often referred to as simply Tann, was a region situated on the planet of Ryloth. Within this province, the Twi'lek Hera Syndulla spent her formative years in her family's home, residing alongside her father, General Cham Syndulla, and her mother, Eleni Syndulla.
During the Clone Wars' Ryloth Campaign, a Y-wing bomber from the Republic crashed within the boundaries of the province. It was in this location that Hera, the daughter of General Cham Syndulla of the Twi'lek Resistance, discovered the astromech C1-10P belonging to the Y-wing, rescued him, and subsequently repaired him. Following the conclusion of the War, Cham chose to leave the Y-wing as a memorial outside of his home.
The Syndulla family's residence was repurposed to serve as an Imperial base of operations.
After the unsuccessful attempts by Captain Slavin, Grand Admiral Thrawn skillfully forced Syndulla to evacuate the Tann province. Subsequently, Slavin and his forces transformed Syndulla's former home into their Imperial headquarters.
At a later point, Kaasha Bateen, a tactician and a fighter for the Twi'lek resistance, was summoned back from her time spent on Pasa Novo during the Pasa Novo campaign. Her return was to aid the Free Ryloth Movement in their efforts to liberate Tann.