Mr Menzies debuted his Asia-centric theories with 2002's '1421: The Year China Discovered the World.' In it, he said that the famed Chinese sailor Admiral Zheng He, who is known to have reached Europe and Africa, also crossed the Pacific Ocean to the Western Hemisphere.
He claims that Zheng He not only reached the New World, he left colonies there. His fleet also sailed around the tip of South America - through the Strait of Megellan around the Gulf of Mexico and up the Mississippi.
There is evidence, both archaeological and genetic, Menzies says, that Zheng He left his mark in California, Florida, Virginia and even the Outer Banks of North Carolina.
In 'Who Discovered America?' Menzies focuses on theories that Asians also made it to North and South America by sea long before even Zheng He.
'It appears certain that man reached the Americas by sea at least forty thousands years ago,' Menzies writes.
'Doubtless this date will be continuously pushed back, probably to 100,000 BC, which was when the first peoples sailed the Mediterranean to Crete and (separately) in the south from Asia to Australia.'
Most scientists believe man first widely populated the Western Hemisphere 13,000 to 16,500 years ago.
The almost universally-held theory among academics is that man came to the New World by crossing the Bering Strait land-bridge between Asia and North America.
'The more I thought about the Bering Straight theory of populating the Americas, the more ridiculous it became,' Mr Menzies writes about his investigation of the topic
Mr Menzies says the idea that man was able to cross the Pacific Ocean around 40,000 BC isn't nearly as dramatic as it seems.
'If you just go out in a plastic bath tub, the currents will just carry you there,' he told MailOnline. 'They just came with the current, it’s as simple as that.'
He added: 'There’s nothing terribly remarkable about. Man has been seafaring for vastly longer than convention credit has given them credit for.'