The Guild of Starlight was founded one hundred and nine years ago by a man named Runcible Ricker. Runcible founded the Guild in order to bring some peace to the area around Savior's Reach, which had become notoriously difficult for travelers. So to foster better trade over land with the nearby towns and villages, he campaigned to start a company that would travel into the wilds and eradicate dens of monsters.
He was met with great success and soon the land became safe near the city. But Runcible was inspired to reach out across the darkness and bring peace to even further lands. He established the Guild in Savior's Reach a little more securely and then took a select group of individuals into the wild lands beyond. That was the last that anyone had heard of him.
Currently the Guild is established in most human towns and villages, as well as few dragonborn and tielfing settlements. There is a single Guild House on Teshyrr. The dwarves and elves have claimed they have no need of its services.
Although no campaign has been as successful as Runcible's original, the Guild is still the go-to mercenaries for rooting out monsters and peacekeeping. While there has a been a slight backslide in the region around Savior's Reach, the Guild has still been moderately successful in keeping their charges safe.
One thing that hasn't changed is the Guild's desire to expand. Frequent expeditions to establish new Houses in the wild and bring safety to new areas are sent out almost yearly. Unfortunately, they are rarely successful and most of these Houses either fall abandoned, or are never built at all. Those that are successful are the centers of new towns and villages. Occasionally a group of members will attempt to seek out the failed houses for their supplies. This is called 'House Hunting'. Not many succeed in even finding the old Houses but most make it back alive.
New recruits are plenty in the heavily populated areas, and even the remote locations get new blood at least a few times a year. A job in the Guild is good money for those that survive and the prospect of bringing in supplies and reclaiming land is tempting for even the most skeptical of villagers. Advancement is fairly quick for those that prove themselves and Guild members are swapped between Houses for replenishment or just a chance to see more of the world.
Leaders are chosen by merit, so it is by mere coincidence that the current leader, Davin Ricker, is a descendant of the Guild's original founder.