Final answer:
The Pax Romana is the period of peace and prosperity that lasted 207 years in the Roman Empire, initiated by Augustus. It saw the reign of three distinct Roman dynasties and included a time of splendid geographical growth and rampant prosperity despite some boundary conflicts.
Step-by-step explanation:
The period of peace and prosperity that lasted 207 years is (a) Pax Romana. Initialized by Augustus, the first Roman Emperor, Pax Romana was a significant era of peace in the Roman Empire lasting approximately 200 years, until the end of Marcus Aurelius' reign.
The Pax Romana spanned across the reign of three distinct dynasties, namely The Julian dynasty, The Flavian dynasty, and The "Five Good Emperors". This era represented the Roman Peace, a time when it was possible to travel throughout the Empire's boundary under the official protection and enjoy the common trade language.
During Pax Romana, the Roman Empire reached its greatest geographical expanse and height of power. Despite intermittent conflicts at the Empire's border, the citizens continued experiencing peace and prosperity, contributing to the period's referential identity as the High Empire.
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