The Seventh Division was a division of the Alliance to Restore the Republic's fleet, formed in 3 ABY when the fleet scattered after the Battle of Hoth.
The Seventh Division was a naval division of the Alliance Fleet, and as such consisted of several capital ships and sub-capital ships. They included an MC80A Home One Type Heavy Star Cruiser, an EF76 Nebulon-B escort frigate, and a CR90 corvette.
The Seventh Division was formed in 3 ABY when the fleet scattered following the Battle of Hoth. After a battle near Malastare resulted in the destruction of the Eighth Division while the Fourth Division was concurrently attacked, and following the destruction of the Sixth Division, Commander Ellian Zahra of the Galactic Empire intercepted transmissions which she believed to have revealed the Seventh Division, and began tracking it.
She subsequently made a status report to Darth Vader as he travelled in a Lambda-class T-4a shuttle, and reported that she was tracking the group's movements and waited, hoping for it to make contact with another division and reveal its location. Vader acknowledged Zahra's efforts and to continue with the operation, additionally stating not to leave a single Rebel ship. The briefing was interrupted, however, when Vader sensed Luke Skywalker in the Jedi outpost on Tempes.
The Seventh Division sent the Fourth Division a transmission concerning a standard rendezvous conformation and they responded even though it meant sending Zahra's forces to both of their locations. Things weren't turning out so good for the Seventh Division during the Battle at Elessia but things started to turn around once the Fourth Division arrived and they used their combined firepower to scare the Tarkin's Will away.
Later the Seventh Division would lend some of their elite pilots for the Fourth Division's Starlight Squadron who would play a key role in Operation Starlight which was a mission to find and bring the other lost cells back to return the Rebellion to full strength.