RKS is named after a famous legendary Magus named Rosenkreuz, who devoted his life to protecting the Magi and helping them live lives free of fear and persecution. When he sacrificed himself for the sake of his people, his final wish was granted, and in return, the formerly magic-loathing-and-persecuting Holy Empire and Orthodox Church allowed the Magi to live on as its subordinates. The organization of RKS was born, and since then, the Magi had been servants of the Empire.
As a few decades passed, a Magus named Iris Sepperin manipulated RKS into believing that they were the target of persecution again and launching a new coup against the Empire in an attempt to claim dominance over it, end their persecution forever, and build a world just for Magi. Eventually, everybody learned the truth about Iris, and Spiritia Rosenberg defeated Iris for everyone's sakes.
RKS is responsible for the work the Empire does on magic research, and they help out as part of their military. It is also rivals with another magic-user organization known as the Schwarzkreuz, who attacked it a few months after the events of the first Rosenkreuzstilette, beginning a witch-hunt for the Magi associated with it in an attempt to put down the Walpurgisnacht for the sake of the Church. They later became neutral to RKS after Eifer Skute's betrayal against them and murder of their respective pope.
RKS has three known divisions; the RKS Strike Force, led by Sichte Meister, the RKS Special Ops division, led by Dolis Warmind, and the RKS Intelligence division, which Karl Palesch is an agent of.
- RKS001 Eins: Spiritia Rosenberg
- RKS002 Zwei: Freudia Neuwahl
- RKS003 Drei: Zorne Sepperin
- RKS004 Vier: Trauare Wrede
- RKS005 Fünf: Luste Teuber
- RKS006 Sechs: Grolla Seyfarth
- RKS007 Sieben: Sichte Meister (RKS Strike Force leader)
- RKS008 Acht: Liebea Palesch
- RKS009 Neun: Schwer-Muta Casasola Merkle
- RKS013 Dreizehn: Dolis Warmind (RKS Special Ops division leader)
- Karl Palesch (RKS Intelligence division member)
- The organization's initials are pronounced "Err-ka-es," which is the same pronounication as the company that produced Rosenkreuzstilette, [erka:es]. This often leads fans to also call RKS by the same name as the company itself.
- The RKS numbers used for the members of RKS refer to the serial numbers that most of the robots and Robot Masters in the Mega Man series. They all share a series of three alphabetical characters followed by a 3-digit number.