“Excessive” inequality seems not to have been brought by Columbus, nor by colonial powers for several centuries, but largely after independence in the 19th century:

Compared with the rest of the world, inequality was not high in pre-conquest 1491, nor was it high in the post-conquest decades following 1492. Indeed, it was not even high in the mid-19th century just prior Latin America’s belle époque. It only became high thereafter. Historical persistence in Latin American inequality is a myth.

That certainly surprised me. I learned otherwise when I was an undergrad.