A studbook society was founded in 1879 by Frisian farmers and landowners who had gathered to found the Fries Rundvee Stamboek (FRS) The "Paardenstamboek" ("horse stud book") was published in 1880 and initially registered both Friesian horses and a group of heavy warmblood breeds, including Ostfriesen and Alt-Oldenburgers, collectively known as "Bovenlanders".