The Aegis Network was developed as a response to a human-led hunt for monsters and witches in the mid-1400s. Initially, they were only working to hide and shelter creatures from human detection, but over the next couple centuries developed into the organization they are today. By the time the witch-hunts ended in the mid-1700s, the Network were a thriving underground organization dedicated to helping where they can and keeping humans naive to ensure something like that Never Happens Again.
So they began to expand. They spread from Europe to the Americas, linking with small, like-minded communities of supernatural beings to create a broader web. There was strength and safety in numbers. It also allowed them to tap into the very useful abilities of others - for warding their safehouses and headquarters, sending messages and warnings more quickly and securely than the early days of postal service would allow, and far more.
With technological improvements, some of those safety measures became easier to do without magic or other unexplained phenomena... But the mission became harder. Photography made it easier for humans to capture evidence of their existence. Phones made it easier to report. Computers and the Internet provided the lynchpin of access that helped information spread so much more easily. There were forums now and chat rooms that made organizing hunts for "creatures" like them a snap...
But it has also made finding each other easier.
The first house the Aegis Network acquired on Ashwood Circle was in 1897. Back then there were only three of them in Chicago, just a couple of witches and a ghost, but the house was paid for and the mission was clear: Find others like them, and if they could, help them. If they couldn't... Well. There were solutions for that, too.
They never knew whose name was on the deed, exactly. Someone at the head of the Network, from somewhere mysterious like Europe. But when they started to expand - bit by bit, a werewolf here and a daywalker there - that same benefactor was there to buy up the next house over in 1932. The third house in the row was bought up in 1957. By then, they were calling it The Row.
1450 - Witch hunts began in earnest, prompting a response from the supernatural communities who did not particularly want to be hunted.
1461 - The Chowdhury family of witches join from Varanasi and offer to hide witches fleeing from Western Europe. Many of these intermarry and eventually return home to help found the London branch of the Aegis Network.
1487 - Many werewolves, or lycanthropes, joined the Aegis Network, finding themselves targeted by the hunts.
1710 - By this time, the Aegis Network had spread to the "colonies" as well, and had become a fairly functional protective force for supernatural beings.
1829 - The first Jackalope was discovered, and brothers Douglas and Ralph Herrick of Aegis quickly stepped in to forge a taxidermied version. Locals seemed convinced.
1896 - The Parker family brokered the connection of the spiritualist commune of Cassadaga, Florida to the Aegis Network, bringing in a number of mediums and psychics.
1897 - The Aegis Network moved into Chicago, purchasing a home on Ashwood Circle.
1932 - The second home on Ashwood Circle was purchased by the Aegis Network.
1957 - The third home on Ashwood Circle was purchased by the Aegis Network, by which point the trio of houses becomes referred to affectionately as "The Row."
1967 - "Bigfoot" first recorded on video; the Aegis Network have been trying to convince the family of sasquatches responsible for these sightings to hide better ever since. Mostly unsuccessfully.
1996 - Present day.