The blood oath (Hungarian: vérszerződés, lit. "blood contract") was, according to tradition, a pact among the leaders of the seven Hungarian tribes, traditionally held to be the first, unwritten constitution of the Hungarian nation. Its story, along with the terms agreed upon in it, is mostly known from the somewhat unreliable Gesta Hungarorum, a chronicle written between 1196–1203 and is thus possibly influenced by 12th century laws and customs. The oath was sealed by the seven leaders – Álmos, Előd, Ond, Kond, Tas, Huba and Töhötöm – by cutting their arms and letting their blood into a chalice. Becoming blood brothers is likely to have been used traditionally to seal exceptionally strong oaths, and there must have been several similar oaths, but the phrase "blood oath" usually refers to