"Who do you serve, and who do you trust?"
- – Galen's question
Galen was born in 2237, the child of two techno-mages, shortly afterwards Elric was assigned by The Circle to monitor his development. Galen's parents would fight often, leading his mother to become increasingly dissatisfied with his father's persistent womanising with Alwyn.
In 2247, both of Galen's parents die when they both kill one another following a heated argument. Following their deaths, Galen is taken in by Elric, becoming his ward and his pupil. Around this time Galen decided that he wanted to be a healer, a desire that would stay with him all the way to age 18.In 2255 Galen attended a Convocation of The Circle where he chose the name 'Galen' for himself, taking it from Aelius Galenus, an ancient Greek physician and philosopher. However, he found he had no aptitude for healing. 
"When he took me in after my father died, I spent most of my life being afraid of him because he was tall and powerful, and that voice...and because I was afraid that I might lose him, too, just as I'd lost my father."
- – Galen to Alwyn
In 2258 Galen is inducted into the techno-mage Order. Early in his career he was said to have focused too much time on spells and not their presentation. Also, he had not yet developed his own style, instead mimicking the incantations of earlier techno-mages.
Galen and fellow Techno-mage, Isabelle, shared a very brief but intense relationship toward the end of 2258. Though the two were only involved for a short time, they developed a relationship in which they could speak volumes to one another without saying a word. As Galen would say of her "She would make you happy with one word, hello." Her abilities as a techno-mage were at least on the same level with Galen.
Shortly after their initiation as Techno-mages, he was partnered with Isabelle in an assignment to gather evidence of the Shadows' return by tracking the movements of their allies on her home world of Zafran 8.
Not long after leaving Zafran 8, they traveled to Brensil 4 where they met with Elizar. After many attempts at convincing the two that there was a conspiracy within The Circle that they knew about the Shadow threat, Tilar who was a rogue Techo-mage appeared to them and proceeded to open fire at the two loyal Techno-mages. Isabelle was dealt a mortal blow by the rogue Techno-mage Elizar. Soon after this, she succumbed to her injuries and died. Just prior to dying, she reassured her distraught beloved, that if there was a way, that she would contact him from the afterlife.
Matthew Gideon was the sole survivor of an attack on the EAS Cerberus, which left him floating in Space. Gideon was picked up by Galen, who later dropped him off at Omega VII.  Galen along with his fellow techno-mages were not in that region of space by coincidence, they were themselves tracking the moments of the unknown Shadow tech vessel that eventuallly destroyed the Cerberus. 
Warning Sheridan about the DrakhEdit
In 2267 Galen appeared in a dream to Interstellar Alliance President John Sheridan. Galen warned President Sheridan that if he did not act soon that Earth would suffer the same fate of Daltron 7, a dead world. Galen then later revealed that the Drakh had a Shadow Death Cloud and that the destruction of Daltron 7 was simply a test, and that they want revenge on Earth because they had defeated their masters, The Shadows. Shortly after this Galen was banished from his order for having too much contact with the humans.
Joining the CrewEdit
In 2259, Galen saved Gideon from death when he and the other techno-mages were leaving known space because of the Shadows. After this, Gideon did not see Galen for several years. Shortly after the Drakh attack, Dureena Nafeel told Gideon of Galen and Gideon set out to find him. Once Gideon found him Galen questioned him and his mission and then agreed to join the crew. Gideon and Galen are, for the most part friends who work together well. But, at times, each would become irritated by the other. Indeed, it can argued that Matthew is Galen's only friend as Galen was expelled by the others like him for breaking the rule about not communicating with the outside world when he spoke to John Sheridan. Because he was not a member of the crew, he frequently come and go as he pleases.
On Regula IV they came across Elric's old friend, Alwyn. They tried to stop Earthforce from mining a mineral that was ruining the land and poisoning the locals. They succeeded by creating an illusion that the techno-mage was trying to destroy the ships in orbit. The Excalibur destroyed the illusion and in the process destroyed the mine.
When they reached a planet to explore he told them not to go down there because the techno-mage would did was killed by what he called a spirit. They went down anyway. When the crew started to die, Dr. Chambers examined the bodies and found out that a nano-virus caused they people to die. Galen asked her to zoom in on part of the virus and he figured out that the nano-virus was made by a techno-mage. He goes down to the planet and puts on a protective shield. He then went down to take out the techno-mage. He found that the techno-mage had long since died, but a hologram of him and a huge machine remained.
When Galen tried to destroy it Dureena, who was under the control of the virus, appeared and tried to kill him. She threw a dagger into his shoulder, and then proceeded to charge at him when Gideon appeared and blew away the bridge she was crossing. She made it over and Galen throws his staff at the machine, which destroyed the machine. When Dr. Chambers treated his wounds she found cybernetic implants in his back. He said that the staff was a one of a kind control mechanism and he needed it back, which moments later Dureena, covered in mud, dropped at his feet. Galen then helped Dr. Chambers modify the virus to be a filter which would temporarily block the Drakh plague.
Ancient Civilization Infected with the PlagueEdit
When Gideon was being chased by robotic ship he saved Gideon in the nick of time. He then says no to Dureena when she asks for him to teach her what he knows. He then gets out a hologram of himself. Except it is modified so that it has more substance. He finds out that other races had been there. When the other hologram appears he figures out that the aliens were conducting experiments on other creatures to find a cure for the plague.
Well of ForeverEdit
"Care no more to clothe and eat; To thee the reed is as the oak."
"The sceptre, learning, physic must. All follow this and come to dust."
"All lovers young, all lovers must. Consign to thee and come to dust."
- – Galen's lament for Isabelle
In July 2267, Galen suggested that they search for the Well of Forever in Hyperspace. Galen patched his ship navigation systems in to the Excalibur and they went searching for it. When they got to the place where it was supposed to be it wasn't there. Galen then took control of the Excalibur and looked in another location. He found the Well and went to it. He took his ship to it and buried his lover, Isabelle. She had long tried to find the Well of Forever, so Galen had made it a mission to find the place and leave her remains there. Gideon was mad at Galen and Galen apologized. Galen then erased the data about the Well from the computers, after which the ship departed.
Warning Sheridan about Prince VintariEdit
Galen approached Sheridan once again in 2271, to warn him of another threat to Earth. In 30 years time the Emperor of the Centauri Republic, Dius Vintari, will destroy Earth, as they are the only people standing in the way of the expansion of the Centauri Republic. Galen informs Sheridan that "there are ways to fix this", and thus Sheridan should kill Vintari. Sheridan arranges for both Sheridan and Vintari to make the final approach to Babylon 5 in a pair of Starfuries. Galen arranges for a "malfunction" in Sheridan's weapons system in which Vintari's Starfury will be destroyed. However, before this occurs Sheridan realizes Galen used the word "ways" rather than "way". So Sheridan disarms the weapons system and instead starts a friendship with Vintari in the hope that he can show him that Earth is no threat to the Centauri. Galen warns Sheridan this path is by no means certain and may fail, he then disappears once again.
|Main Characters (Crusade)|
|Captain Matthew Gideon Captain Elizabeth Lochley Lieutenant John Matheson Max Eilerson Galen Dr. Sarah Chambers Dureena Nafeel|