*All countries have been conquered at some point in history except Nepal(supposedly)...everyone forgets Nepal, they have never been conquered neither occupied by any other nation.*
*Otherwise, as for as i know, each and every country has been either occupied or conquered or ruled by another one at least for some time in the last 3000 years.But this is supposedly, it has not been proven 100% yet.*
*England was conquered by the Romans.*
*Also contrary to popular belief, Scotland has been conquered by England,In 1652 the forces of the English Republic under Oliver Cromwell completed the military conquest of Scotland, imposing an English government regime which was supported by 10,000 troops and a network of fortresses, lasting until the restoration of the monarchy in 1660.subjugated by English many times, including the rule of King Edward Longshanks and Lord Protector Oliver Cromwell.*
*USA, Canada, Mexico, and Americas- Native Americans conquered and land colonized*
*Australia- Aboriginal defeat at the hands of the British*
*Japan- US occupation following WWII*
*Thailand- Japanese during WW II*
*Afghanistan- ALEXANDER THE GREAT*
*Nepal can be argued for, although it served as a vassal state of the Gupta Empire and also under the incredible influence of the British Empire.*
*Sweden, which has maintained its sovereignty throughout history has had many unions with other countries, becoming semi-autonomous, most notably the Kalmar Union. During World War II, the Swedes served at the whim of the Third Reich of Germany, although they pleaded neutral, like Switzerland.*
*Bhutan has some claims, for records of the period between the 7th and 9th centuries are sketchy. Claims have been made that the Kamarupa Kingdom or Tibetan Empire conquered it during this time. The British and Indians have also had considerable influence.*
*So most countries have never remained autonomous. And Sweden, Nepal, and Bhutan (which has sketchy history) have come under major influence.*
*Ethiopia has never been colonized in its 3000 years history except the 5 years occupation of Italy.*
Ethiopians were able to defeat Italy in the Battle of Adwa in 1896 and became the first black nation to successful repel colonization.
*The five year occupation may disqualify Ethiopia from being one of the countries that have never been "conquered."*
*But if we consider occupation as being "conquered", all the countries that are listed above have been "conquered" since they have definitely been occupied not ruled by some other people at some point in their history.*
http://in.answers.yahoo.com/question/index?qid=20110915141648AA3XV0B