Final answer:
Baron von Steuben was the former Prussian Officer who trained the Army at Valley Forge and wrote the "blue book" regulations for the troops of the United States.
Step-by-step explanation:
The name of the former Prussian Officer who provided training to the Army at Valley Forge in the winter of 1778 and wrote the "blue book" regulations for the order and discipline of the troops of the United States is Baron von Steuben. Baron von Steuben was a key figure in training the Continental Army during the American Revolutionary War, helping to turn it into a more professional and disciplined fighting force. His contributions were instrumental in the eventual success of the American forces.
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