The real lesson I got from the history was: don't get conquered.
The Mongols conquered and partitioned Rus in the 1200s, and they are still fighting along those lines to this day like the Hatfields vs McCoys.
It would be like China conquering the US today, partitioning the US into 3 western, northeast, and southern states, and then Americans effectively fighting a civil war between those 3 factions for a thousand years until the year 3000.