When different civilizations interact, whether that be through trade or war, there is typically a language barrier between each civilization. In terms of the history of the United States, it would have been impossible for Native Americans and English settlers to communicate and resolve their differences without the aid of Pocahontas or for Lewis and Clark to navigate through tumultuous tribal regions of the Western continental United States without the help of Sacagawea.
Nearly two millennia before the efforts of Sacagawea and Pocahontas allowed for success on the western frontier, the Rosetta Stone had a similar effect in the East. The Rosetta Stone is a rather large (4ft x 2.5ft x 1 ft) block with three different scripts, two of Egyptian and one of Greek. Academics used the stone as the primary method of learning hieroglyphics, a language that had been lost to even the Egyptians since ~300 A.D. The fact that the stone wrote the same phrase in each script, allowed scholars to utilize the relatively common fluency in Greek and extrapolate that to the Demotic Script (a more modern script of Egyptian) and then finally decipher the meaning of the individual hieroglyphics.
However, the original purpose of the Rosetta Stone was not to allow scholars a method of deciphering ancient hieroglyphics but rather served as a method for allowing Greeks to understand the literature behind Egyptian Gods. The Rosetta Stone is a smaller portion of a religious text, intended to allow those near the temple to understand its purpose.
This is a common theme among ancient civilizations, with literacy rates abysmal, no public education, and few secondary language skills among the average population, the language barrier was about as significant as it could be. That being said, individuals still needed to communicate and there was a clear desire to break it down. While the Rosetta Stone is one of the few remaining and intact methods of the first translation services, the energy and care taken into making the Rosetta Stone showcases the desire to communicate freely.