|Full name:||Gideon Arthur Lightwood|
|Age:|| 20 (as of 1878)|
60/61 (during death)
|Family:|| Sophie Collins (wife)|
Barbara Lightwood (daughter)
Eugenia Lightwood (daughter)
Thomas Lightwood (son)
Benedict Lightwood (father)
Barbara Pangborn (mother)
Gabriel Lightwood (brother)
Tatiana Lightwood (sister)
|Hair color:||Sandy blond|
Early Life Edit
Gideon Arthur Lightwood was born the eldest of three children, the others being Gabriel Lightwood and Tatiana Lightwood. Their mother died when he was five years old, and the story of her death that their father told them never made sense to him. Raised by their father, Gideon and his siblings grew up believing all Shadowhunters were like Benedict, who flouts convention and the Law, and they all acted like it. Gideon, however, had apparently never been happy in London, calling their home a miserable place ever since his mother's death.
Gideon was about fifteen when he met Will Herondale at a Christmas party held at the London Institute. His sister, Tatiana, was hopelessly infatuated with Will. When Will humiliated her by reading her diary in front of the entire Enclave, Gideon and Gabriel developed a deep loathing for Will, though Gideon was fairly calmer about it than his brother.
When he completed his Shadowhunter training at eighteen, Gideon opted to travel to another Institute and settled in Madrid. Gabriel was shocked to realize that all Shadowhunters weren't as pompous as his father and was apparently treated like a monster until he realized the wrongness of the principles he was brought up with and changed his ways.
Return to London Edit
Around a year after he left to travel, Gideon was called back from Madrid by his father. He was told that he was needed at home, and that he must return immediately. Therefore, despite his wish to stay away, he embarked on the journey home. He only did so in hopes of helping his brother, Gabriel. Though he no longer agreed with his father's decisions and principles, he agreed to return home and stay for Gabriel's sake, worried that their father would continue to brainwash him.
He and Sophie began to meet when Sophie wasn't working. Sophie began to greatly love him, and he her. When the Shadowhunters of the London Institute needed someone to watch the Institute while they were out, Sophie recommended Gideon. He then became the one that they often called when needing someone to watch the Institute.
Gideon attended a party that his father held and he was disgusted to discover that his father was fraternizing with demons; an act which is illegal in Shadowhunter culture.
Automaton War Edit
When the rest of the house goes to fight Nathaniel Gray, he claims to be helping Sophie train, but he and Sophie are seen, by Tessa, talking and whispering, intimately.
When the members of the Institute came to blackmail his father, Gideon sided with them in the confrontation. He feared the future of the Enclave, the London Shadowhunter force, if his father became head of the Institute. Then, he left with the Institute Shadowhunters, deciding to take up residence at the Institute.
He sat with the Institute Shadowhunters at the Council meeting.
He is still in love with Sophie, and thus hid the scones that Sophie had to carry around, under his bed, this makes Sophie angry because he was making her overwork. However, Gideon later proposes marriage to Sophie, and she agrees.
In Cadair Idris, he fought alongside Gabriel, and returned alive.
Later life Edit
While the Lightwoods became a laughing stock because of his father's actions, Gideon and Gabriel worked hard to regain their family's honor. 
Gideon apparently died in 1919.
Physical description Edit
Gideon is described as very attractive. He was very muscular and had thick, sandy-blond hair and grayish-green eyes.
Gideon is exceptionally different from the rest of his family. Like his mother, Gideon is mature and kind-hearted, as well as quiet in nature and typically calm. He is known to be a fairly good teacher to Sophie and he is far less rash than his brother. He is shown to care very deeply for his brother, returning to London, though he hated his father's home, just to help his brother.