[mytailorisrich]

Relative population levels are indeed important to understand how colonisation could have happened, in addition to technological superiority.

An example involving France, and which had long lasting consequences: in 1830 France invaded and conquered Algeria. Looking at those with modern eyes one might think it should have been a massive war with an untenable outcome because France has a population of 68 million and Algeria has a population of 46 million... but in 1830 France had a population of about 33 million and had industrialised while Algeria had a population of only 3 million and still had an agrarian economy so the dynamic was completely different (although it still wasn't a walk in the park for the French).