“Quagmire” is a combination of two words in English that both basically mean “swamp,” but each has different origins. “Quag” is a variation on the Middle English “quabbe” (meaning “a marsh”) and the Old English “cwabba” (meaning “soft thing”). “Mire” has Scandinavian roots: the Old Icelandic “mýrr,” and the Norwegian, Old Swedish, and Danish “myr.” Both “quag” and “mire” are independent words in English (“quag,” meaning “marsh” or “bog,” and “mire,” meaning “area of mud or spongy earth”), but “quagmire” is used more widely than either.