@prettybird
The list (as opposed to the narrative) in that link doesn't make sense
For example, it includes India in the list of countries that were never colonised 
and USA, Zimbabwe, Ireland, NZ, Australia, Namibia, Algeria, to name a few that have been mentioned on this thread.... 
The link says
“Very few countries have never been either a colonizing power or become colonized. They include Saudi Arabia, Iran, Thailand, China, Afghanistan, Nepal, Bhutan, and Ethiopia.”
False statement. Every country had at one time been colonised and/or a coloniser.
Saudi Arabia- colonised by the ancient Egyptians, North African berbers, Hyksos, and Islamic and Ottoman Empires
Iran- sent out and had waves and waves of colonising invaders all through ancient times to almost modern times (1800s). From akkadians to Sumerians, to Hittites, to Persians, to Romans to Ottomans.
Thailand- Was formed by migrating Tai colonisers from Nanchao (now Mainland China) who then formed their own kingdom.
China- colonised and taken over-by the Mongols for one. And invaded and colonised much of Central Asia, how do you think it is so big? Many smaller kingdoms were simply swallowed up. Tibet was invaded by and ruled by China for centuries. Taiwan was colonised by China in the 1600s before given to Japan in a treaty.
Afghanistan-colonised and ruled by the Persians, by Alexander the Great. Invaded and ruled Pakistan for a few centuries as its own empire of Bactria. Bactria, then fell to the Mauryan Empure out of India and Afghanistan was colonised again, gaining Hinduism and bhuddism. Stayed colonised under other Indo empires, until finally independent and formed their own Kushan empure during which Afghanistan then colonised much of India and east even into China. This lasted until we have an Iranian Empire Sassanids invading and colonising. They lasted until the Islamic Empire invaded.
Nepal- or Gorkha kingdom was originally a medieval colony of Brahmin Indians moving away from Muslim advances from the west. They invaded and conquered the area and set up Nepal. Ruling until the Shah dynasty was abolished in 2008.
Bhutan- invaded and colonised both by Tibet, the Mongols in its history and in the 1770s it invaded and colonised the kingdom of Koch Bihar. The rulers of Koch Bihar asked the British for help who managed to oust Bhutan back to their original borders and protect them for next hundred years.
Ethiopia- invaded and colonised Sudan (known as Kush) and Yemen during its Aksumite Empire days. Their empire was so large, it bordered Roman controlled Egypt.