- Professor Oak was born Yukinari Ohkido in Japan in the early 1900's. He could always perceive the supernatural, and took a great interest in it. Still for the early part of his life, he did his best to fulfill expectations. He got married, he had a couple kids. While he wasn't a BAD father  or husband - it was pretty clear his passions laid with his research rather than family life.

-  Whenever he could, Ohkido would travel to the Spirit Realm and learn what he could. Unfortunately he got a little reckless and absent minded- which caused him a near death experience and made him begin to remember his past life.

- Which unfortunately meant the Black Order came knocking at his door. Ohkido was recruited and served as a Guardian for a number of years. To say he disliked the work would be an understatement.

- During a mission in the realm of Vourukasa, Ohkido came across a badly injured Arceus that had managed to stumbled in there. Wanting to help the creature, Ohkido offered up his own life energy to heal it. While it successfully healed Arceus, it sapped Ohkido of his youth and left him physically an old man. To keep his savior from dying, Arceus insisted he eat from the tree within the realm. It  worked and gave Ohkido immortality - but he was still stuck as an old man.

- After that, a strong friendship was formed between Ohkido and Arceus. Once it had recovered enough of its strength, Arceus used its power to fake Ohkido's death and shield his presence from the Order's magic sensors. Fortunately the ruse was helped by the  fact that Ohkido was now several decades older in appearance than anyone remembered. He changed his name to Samual Oak and began traveling the world to figure out his place in it.

- It was sometime after this that he met Persephone!

- Over time, he began to formulate the idea of POKEGO. Not only did he want a group of like minded people to study the Spirit Realm, but he wanted to possibly provide refuge to those who were like him and wanted nothing to do with the Order. POKEGO eventually came from that desire and it took him quite awhile to  set up all the resources.

- The tree codenames are enchanted with Arceus's blessing. So long as you have one, the Black Order's sensors cannot detect them.

- Gary is more his great-grandson than his grandson, but honestly who is counting anymore.