Most if not all of the examples you mention, the conquering nation pacified the conquered essentially with genocide. Take, for example, Caesar conquering Gaul [

Most if not all of the examples you mention, the conquering nation pacified the conquered essentially with genocide. Take, for example, Caesar conquering Gaul [1]: > The term "Celtic Holocaust" was popularized by the podcaster Dan Carlin in a 2017 podcast, in which he made the case that the Roman Republic's actions during the Gallic Wars constituted a genocide. Of the 3,000,000 Celts who inhabited ancient Gaul, one million of them were massacred, while another million were enslaved; this signifies that Gaul lost two-thirds of its population in a case of bellum romanum ("war in the style of the Romans", or total war). In fact pretty much any Roman conquest involved a lot of slaughter and enslaving a large portion of th eremaining able population. Another example: the Mongols [2]: > Ancient sources described Genghis Khan's conquests as wholesale destruction on an unprecedented scale in certain geographical regions, causing great demographic changes in Asia. According to the works of the Iranian historian Rashid al-Din (1247–1318), the Mongols killed more than 700,000 people in Merv and more than 1,000,000 in Nishapur. The total population of Persia may have dropped from 2,500,000 to 250,000 as a result of mass extermination and famine. [1]: https://historica.fandom.com/wiki/Celtic_genocide https://historica.fandom.com/wiki/Celtic_genocide [2]: https://en.wikipedia.org/wiki/Destruction_under_the_Mongol_Empire https://en.wikipedia.org/wiki/Destruction_under_the_Mongol_E...