Carannia was the capital city of the Outer Rim Territories planet Serenno. It shared its name with Carannian fur which was worn by Serennian Senator Izzet Noor during the High Republic. During the last years of the Galactic Republic, the city adopted the same anti-Republic stance as Fiyaro and Saffia. By the end of the High Republic era, Jedi Initiates Dooku and Sifo-Dyas visited the city during a festival that saw the city booming with visitors. In the late Republic era, the city was invaded by Abyssin Mercenaries hired by Count Ramil leading to much of the city being destroyed. This caused Dooku to replace Ramil as Count of Serenno. By 23 BBY, much of the city was rebuilt under Count Dooku using the profits gained from processing a seam of sacanium near the city. Dooku's reign however saw unemployment in the city spike with workers being replaced in favor of droids. In 23 BBY, Sith assassin Asajj Ventress was tasked with finding Jenza, Dooku's sister in the city where she found and killed Jenza under orders from Dooku. During the Clone Wars, former Sith assassin Ventress and a group of Bounty hunters landed at the local spaceport in the city. In the Imperial era, Corellian smuggler Han Solo landed at the same spaceport sometime before 0 BBY.
The city was located along the shoreline of the Belsallian Sea, near the Carannian hills. The city consisted of vaulted structures and cylindrical towers that extended to the forest-covered hills of the mountain range nearby. Much of the grand architecture in the city complemented the natural surroundings of Serenno's flora. The city contained the Carannia Spaceport which was also known as the Serenno spaceport that housed many starship classes such as bulk cruisers with its design being sympathetic to its natural surroundings. The city also contained various government facilities such as the Great Assembly House, an enormous cathedral with a large domed ceiling which housed the Planetary council of Serenno. By 23 BBY, close to the Carannia spaceport was the Trannon district where the Portmaster's office was situated which controlled space travel to and from the local spaceport. The Belsallian Cantina, a spaceport cantina, was constructed by this time. Many warehouses were also situated inside the city with one notable warehouse being close to the cargo stores that were near a crumbling res block.
In 90 BBY, a grand celebration took place in the city leading to many visitors coming to see the city and the festival which included Jedi Initiates Dooku and Sifo- Dyas. While Dooku and Sifo Dyas were talking and exploring the city, Dooku noticed Jenza in the crowd after running off from her droid caretaker D-4. Sensing that he knew her somehow, Dooku followed Jenza. Making sure that Dooku didn't get in trouble, Sifo Dyas followed him. While Dooku followed Jenza, Jenza was robbed by a thief. Determined to get back her purse and a crystal belonging to her grandmother, Jenza confronted the thief. This led to the thief and his allies to harass Jenza and later Ramil. Before any further escalation could occur, Dooku intervened and fought the thief and his friends. After Dooku fought and won the fight, Jenza gave Dooku a tour of the city including the Great Assembly House. While exploring the Great Assembly House, a carving of the Tirra'Taka drew Dooku's attention. When Dooku touched the carving, a sudden groundquake caused the structure to collapse. This led to the Jedi Masters and rescue droids rescuing the two children from the rubble. Right after the two children were rescued, Count Gora was angry with Grand Master Yoda of bringing his Force-sensitive son, Dooku to Serenno. After ordering the Jedi to leave, Dooku and the Jedi Masters left the city and the planet.
When Ramil became Count of Serenno, he allowed pirates to raid Serenno leading to the Great Houses hiring Abyssin mercenaries. The mercenaries were bought out by Ramil who organised the Invasion of Serenno with the mercenaries taking control of Serenno and the city which led to much of the city being destroyed. Outnumbered by the mercenaries and receiving no help from Ramil, Jenza, acting on behalf of the resistance group fighting the mercenaries, requested Jedi Master Dooku for help. After failing to convince the Jedi Council to help the planet because Ramil refused to pay taxes to the Republic, Jedi Masters Dooku, Sifo- Dyas and Lene Kostana travelled to the planet in the Truthseeker where they were fired upon by the mercenaries. After crash- landing in the Delgaldon Plains and meeting up with the resistance group, Dooku led the assault on a nearby outpost close to the city and took over the outpost. Immediately after Dooku and the Serennian resistance group took over the outpost, Ramil and his droid army intervened and ordered Dooku, Sifo Dyas, Kostana and the rest of the resistance group to surrender. After surrendering, Dooku was summoned to the Windrunner, Ramil's airship, where Ramil mocked and tortured Dooku of how he will sort Serenno by removing the Great Houses governing the planet thereby removing the infighting that led to multiple crises on the planet. When Ramil ordered Jenza killed by his own lightsaber, Dooku was consumed by anger and controlled the Tirra'Taka, an ancient reptillian dragon, which ravaged Ramil's droid army below. Dooku then took an electrostaff and destroyed the central processor controlling Ramil's droid army. He later killed Ramil using his own lightsaber and was forced to kill the Tirra'Taka after he lost control of the creature. After the battle, a seam of sacanium near Carannia was discovered which was used to help rebuild the city. By 23 BBY, much of the city was rebuilt under the newly appointed Count Dooku.
Although much of the city was rebuilt, Dooku like his predecessors, replaced workers with droids causing unemployment to skyrocket. In 23 BBY, under orders from Count Dooku, Sith assassin Asajj Ventress went to the city to find Jenza who had been kidnapped there. After Ventress barged into the Portmasters office located in the Trannon District, she found out that Jenza was kidnapped by Glute, a Crolute criminal. She later went to the Belsallian Cantina and tortured members of the Razorclaw Gang to find where Glute was hiding. When Ventress found Glute in a crumbling res block near a warehouse, she confronted Glute. Before she could interrogate the criminal, Glute was shot by Republic Intelligence officer Raz Fellidrone who Ventress tracked to his own apartment. After following the officer to his apartment, Ventress managed to find and free Jenza in a secret compartment located in the portmasters apartment. Dooku later arrived and ordered Ventress to kill Jenza and bury the evidence. Ventress obliged and assassinated Jenza then caused a fire that destroyed the apartment and the building where the apartment was located.
Towards the end of the Clone Wars, in an attempt to rescue Jedi Master Quinlan Vos, former Sith assassin Ventress and a syndicate called Krayt's Claw led by Boba Fett landed at the local Carannia Spaceport in the Slave I. After landing at the spaceport, the group travelled to Castle Serenno, the home of Count Dooku, where Vos was held at. At some time in the Imperial era, prior to 0 BBY, Corellian smuggler Han Solo met a girl named Sarla at the Carannia Spaceport in the city where he flirted with her.
Carannia was first mentioned in the Star Wars: Build the Millennium Falcon 70 magazine published by De Agostini and released on May 4, 2016. It later appeared in the script book version of the canon audiobook, "Dooku: Jedi Lost" written by Cavan Scott and released on April 30, 2019. In Star Wars Legends, the location first appeared in the Darth Bane: Rule of Two novel. The city was later pictured in the sixth issue of the Star Wars: Agent of the Empire comic series published by Dark Horse Comics.