The native population of the Spanish colonies (i.e., Native Americans in the area) died off due to wars between Spanish settlers and natives, poor working conditions in enslavement, and the tons of diseases brought over by the Spanish that Native Americans' bodies did not know how to fight all drastically wiped out native Spanish populations. They had to bring in a lot of slaves from Africa to make up for these losses.
A constant and rapid fall of volcanic ash from a large eruption is ideal for preserving what exists upon the land at the time of deposition. So you see we should even preserve the things. It can bury them intact without moving them and without completely crushing or burning them.
