Which country had the smallest population?
Definitely, it's the Vatican. There are approximately 1000 people. But there's the Pitcairn Islands where only 122 people live. But the next independent state after the Vatican is Tuvalu with a population of 10000 people. But the size isn't correlated with a population at all. For instance, Russia is the biggest but the population isn't that great. Yeah, in Moscow live 12 million people but only 140 million people in Russia.
Vatican City