During the Clone Wars, the 7th Sector Army functioned as one of twenty Sector Armies within the Grand Army of the Republic. This army operated in the northern section of the galaxy, alongside other Sector Armies up to the 12th Sector Army. Initially, the Grand Army was structured into ten Systems Armies at the war's onset. Each Systems Army was divided into two Sector Armies, drawing resources from a specific area of the galaxy. The Sector Armies were tasked with defending their designated zones. Therefore, the 7th Sector Army shared a Systems Army with another Sector Army. Like other Sector Armies of the Galactic Republic, the 7th Sector Army was assigned a Haven-class medical station for support. This unit comprised 147,456 clone troopers organized into four corps. In line with other Sector Armies, it was attached to one of the twenty numbered fleets belonging to the Republic Navy.
The first mention of the 7th Sector Army in the new Star Wars canon appeared in Star Wars: Build the Millennium Falcon, specifically in the eighteenth issue of the De Agostini magazine, released in 2015. Prior to this, the Seventh Army was established in the 2012 Star Wars Legends book, The Essential Guide to Warfare, authored by Jason Fry and Paul R. Urquhart, under the name of the Seventh Army.