Reich (n.)
German, "kingdom, realm, state," from Old High German rihhi, related to Old English rice, from Proto-Germanic *rikja "rule" (cognates: Old Norse riki, Danish rige, Old Frisian and Middle Dutch rike, Dutch rijk, Gothic reiki), from PIE *reg- (1) "move in a straight line," hence, "direct in a straight line, rule, guide" (see regal). Used in English from 1871-1945 to refer to "the German state, Germany." Most notoriously in Third Reich (see third); there never was a First or Second in English usage.