Who said "el grito de dolores" and why is it called that?

For over 300 years between 1519 and 1821, the entire country we now know as Mexico was enslaved under the colonial power of Spain. Our people, the natural resources, the land and our government were all controlled directly under the kings of Spain, who sent their agents out throughout our lands to carry out whatever the kings ordered them to do. During that period in history the Spaniards had all the power over our gente, and they did whatever they wanted with us. They treated the great majority of our people like slaves on our own land, and they stole everything they could to take it back with them to Europe, especially native gold and silver.

Explanation:Hope this helps.