Zardnaar
Legend
Also nine tenths of the population has already died from diseases like swine flu (which spread from pigs released into Florida all the way across the country), so all the power structures were a mess. Folks who wanted more power took advantage of the Spanish invasion to take down those in charge.
The 90% is a bit misqouted.
Varied by region and mist died after the Spanish conquest.
Think 90% was more applicable to North America.
It's not like the Spanish turned up, 90% conveniently died and they ate what was left.
It did throw the social structure of the Incas into chaos though.