Answer:
After the Mexican War of Independence against Spain (1810-
1821), most of Mexico's economy reverted to subsistence levels,
due mostly to Spanish capital fleeing the country. This changed
Mexico from one of the most successful countries in the world to
one of the most pauper in just a couple of decades.
Internal turmoil between conservatives and liberals kept a weak
government and institutions. As an example, between 1821 and
1841, more than 30 people took charge and were quickly
deposed as presidents of the country. This of course, resulted in
poor and changing policies and high government costs, such as
military expenses.
Successive internal wars and foreign invasions from the United
States (1846) and France (1862) further weakened Mexico and
increased its foreign debt to astounding levels.
The Mexican Revolution (1910-1921) caused more than 1
million dead to a country with no more than 11 million people.
After the conflict, a "land redistribution policy" ensured rich and
productive lands were given to ignorant, poor people who didn't
know what to tho with them; ultimately becoming highly
dependent on governmentsubsidiesto keep subsistence farming
practices.