The document discusses important dates in Mexican history. On September 13th, Mexico celebrates the Chapultepec battle where six heroes died defending Mexico, including one who carried the Mexican flag. September 16th marks the independent cry, also known as the Cry of Dolores, when Miguel Hidalgo led an uprising against Spanish rule starting Mexico's fight for independence. November 20th commemorates the beginning of the Mexican Revolution as people fought to overthrow President Porfirio Diaz's authoritarian government.