Basil Stag Hare was previously a member of the Fur and Foot Fighting Patrol, as well as an outfit known as the 47th Hare Border Rangers. Due to his admiration for stags, whom he thought as noble creatures, he took his middle name for the creature.

Basil also served as an Officer Cook in the 67th Paw an' Mouth Long Patrol under Colonel Puffscutt.

He was an expert in camouflage, and was well-known for his appetite, as is the case with most hares. He lived alone in Mossflower Woods and became a close ally of Matthias. Soon thereafter, he moved into Redwall Abbey. Basil also knew Captain Snow, whom he had rescued from a fallen tree, and Squire Julian. He and Jess Squirrel recovered the tapestry of Martin the Warrior from Cluny the Scourge, during which he suffered a self-described "honorable war wound."

Basil later had a nephew (or other type of relative), Tummscoff Stag Vittlesmythe, who liked calling him "Nunky Baz." Basil greatly disliked this nickname, and eventually persuaded his nephew not to address him as such.

Basil assisted Matthias in rescuing kidnapped Redwallers from Slagar the Cruel. Throughout the trip, he became fond of Cheek. He also proved essential in the assault on Malkariss' kingdom. Afterwards, he adopted Cheek, who renamed himself Cheek Stag Otter.

In Pearls of Lutra, it is stated that after Basil's death, Redwall Abbey did not have a hare until the arrival of Clecky. Also, when in contact with the plant thyme, Basil would sneeze.

His battlecry was "Give 'em blood and vinegar!".