He had graying hair and wore a black eye-patch over his missing eye. He was of medium height. He didn't think about much else except how to attack.
Finding the Prophet Edit
He was with Berelain when Perrin found the Darkhound tracks and then accompanied Perrin when he looked over the Shaido Aiel camped in Malden. He went with Perrin and Berelain to So Habor, where they collected grain for their troops.
While traveling from Malden, he was with Perrin when they found land that appeared to have been affected by the Blight. Later he attended a meeting with Perrin and others to receive a report on how well the Wise Ones and the Aes Sedai cleaned up the infected land. In that meeting they also decided how the army should deal with the Whitecloaks. During that meeting Seonid and Perrin both confirmed that a Forsaken had occupied Andor for a spell until Rand al'Thor rooted him out. Morgase Trakand, in the personage of Maighdin, was present and requested to be excused.
Encounter with the WhitecloaksEdit
Gallenne was in the army escort provided Perrin as he moved to meet with the Whitecloaks for the first time after Malden. 
After Perrin and Slayer battled in Tel'aran'rhiod, he, along with Gerard Arganda, was consulted about where an ambush would be appropriately set up on the road down which they travel. He was also present or nearby when Perrin, with the help of Asha'man Fager Neald and several Wise Ones, constructed his Power-wrought hammer.
He led the Mayene cavalry in defense of the Whitecloaks in the surprise Trolloc attack that occurred shortly after the conclusion of Perrin's trial, and questioned Perrin about what he owed the Whitecloaks. Perrin's response led him to call Perrin "strange" and "an honorable man." 
Gallenne was killed in the battle outside Cairhien against the Shadowspawn army in the Last Battle. Despite the constant arguments he and Arganda had shared, Arganda mourned him deeply and discarded his own helmet in favour of Gallenne's.