The trick is the mummies had cocaine in the body cells. Cocaine, in that period thousands of years ago was available only in the Andean highlands.
Following up on the idea, a town site that resembles the model prescribed for Atlantas was, in fact, found in the Andean highlands. For what it's worth, you'd better believe some guys from South America with a boatload of blow would be remembered for a very long time in ancient Egypt ~ or anywhere else for that matter.
The peddlers appear to have not returned to America for another load. Else, they'd brought the idea for the bow and arrow with them. It wasn't until about 800 AD that anyone showed up with a bow and arrow in America.
The term Assassin originally referred to a heretical Islamic order known as the Hashshashin. According to one derivation, the word means "those who use hashish" (cannabis resin) in Arabic because, according to Crusader histories, that group used to ingest hashish before carrying out military or assassination operations, in order to be fearless. The group, known as the Nizari Ismailis, was a Shia order who believed in the notion of the hazir imam and was organized as a secret underground political order, which infiltrated areas under the control of Seljuk Turks. In 1090 the sect captured a castle called Alamut in the mountains of Northern Iran. This sect was said to carry out assassinations of the enemies of the order, or Muslim rulers they believed to be impious. The earliest known record of the word in English dates back to 1603, referring to this sect rather than its more general modern sense.