Bree is a Narnian Talking Horse who was captured by Calormen's at an early age. To survive he had to hide his true nature and pretend to be a dumb beast. He was the mount of the Calormen noble Anradin, who is a cruel master but treats Bree well out of necessity. One day Bree and his master spend the night at Shasta's house, and Bree overhears Anradin offering to buy Shasta. Realizing that Anradin will not treat the boy well, Bree reveals that he is a talking horse to Shasta, and proposes that they both try and escape to Narnia together.
They eventually meet up with Aravis and Hwin, and with them, they journeyed north through Calormen in an effort to get to Narnia.
While in Tashbaan, Shasta is separated from the group and Aravis takes charge since the horses must pretend to be dumb and witless. When the group is reunited a day or so later at the Tombs, the group travels across the desert in an attempt to warn King Lune of Archenland of Calormen's impending attack. When the group is ambushed by a lion, Bree bolts in fear; leaving the others to fend for themselves, an act he is very ashamed of later. They reach the home of the Hermit, where Bree, Hwin and Aravis stay while Shasta leaves to warn King Lune. Bree is so ashamed of his actions that he contemplates returning to Calormen, when Aslan silently appears and frightens Bree badly. Bree is able to swallow his pride, however, and accepts Aslan's gentle rebuke for his self-conceit.
Shasta (Prince Cor) turns up later and invites the group to visit Anvard, King Lune's castle. They do, but Bree eventually leaves to settle down in Narnia. He later marries and is numbered among the faithful at the Great Reunion.