In English, the word king is derived from the Anglo-Saxon word cyning, itself derived from Proto-Germanic’s kuningaz. Interestingly, the Proto-Germanic word was borrowed from a language related to modern Finno-Uralic languages (the modern Finnish word for ‘king’ is kuningas).
The Germanic languages’ word for king is quite different from most other language families’. For example, rex, rajan, ri, roi, in Latin, Sanskrit, Irish, and French, respectively.
Earlier terms in Germanic languages stemmed from the idea of ruling over a people, such as the Gothic þiudans, which is related to the Proto-Germanic þiudisc, of which Deutschland is derived.