Ugrin was born into the "gens" (clan) Csák. According to the "Gesta Hunnorum et Hungarorum" ("Deeds of the Huns and Hungarians"), the ancestor of the kindred was Szabolcs, son of chieftain Előd, the leader of one of the seven Magyar tribes, who participated in the Hungarian conquest of the Carpathian Basin in the late 9th century. Accordingly, Szabolcs' grandson was Csák, founder of the namesake clan and contemporary of Grand Prince Géza, then King Stephen I. Historian Gyula Kristó proposed that Ugrin was presumably the son of that "comes" Ugrin, who owned the Vértesszentkereszt Abbey in the Vértes Hills in 1146. Historian Pál Engel considered, Ugrin belonged to the Kisfalud branch of the "gens" Csák. In his last will and testament in 1231, Nicholas Csák, who served as "ispán" of various counties in the first half of the 13th century, referred to Ugrin as his "frater", literally "brother", but it most likely means "uncle" in this context.