I don't really know if he was the first to speak it but Bishop Ulfilas wrote the first Germanic language created in the 4th Century
Explanation:
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Answer 2
The appearance of the German language begins in the Early Middle Ages with the High German consonant shift. Old High German, Middle High German, and Early New High German span the duration of the Holy Roman Empire. The 19th and 20th centuries saw the rise of Standard German and a decrease of dialectal variety