From the Old Norse personal name Rögnvaldr (composed of regin ‘advice, decision’ (also, ‘the gods’) + valdr ‘ruler’). This name was regularly used in the Middle Ages in northern England and Scotland, where Scandinavian influence was strong. It is now widespread throughout the English-speaking world.
Italian and Greek (Tripolis, Tripolitakis): habitational name from any of various cities called Tripoli, a place name of Greek origin meaning ‘triple city’. In particular, there is a place so named in North Africa (Libya), another in Lebanon, and another in the Peloponnese (capital of Arcadia).