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The Mexican Revolution: Displacement and Flight to the United States

1910–1920 · Americas

Displacement Mass Killing

Displaced

400,000

Robert McCaa's demographic reconstruction, using two-sex inverse projection against the 1930 census, puts emigration losses at fewer than 400,000 out of a total demographic cost of about 2.1 million, of which he attributes roughly 175,000-200,000 to war-related refugee movement specifically. Internal displacement was far larger and was never counted; whole districts of Morelos, Chihuahua and Durango were emptied at points in the fighting. The evidence is Mexican and United States census data, US immigration records and McCaa's projections.

Share of the population affected

2.6%

of the population of Mexico at the 1910 census, the last before the Revolution, 1910

Killed

1–2 million

excess mortality incl. disease and starvation

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What happened

The decade of revolution that followed the fall of Porfirio Diaz in 1911 was fought largely in the countryside and destroyed the security of rural populations across northern and central Mexico. Federal and revolutionary armies alike conscripted men, requisitioned crops and livestock, burned villages and, in Morelos, concentrated the rural population under General Victoriano Huerta's commanders in an effort to deny support to the Zapatistas. Civilians left for the cities, for the mining towns and in very large numbers across the northern border, where United States immigration policy was permissive until the 1920s and where the Mexican-descended population of the south-west grew rapidly. McCaa's reconstruction puts the total demographic cost of the revolution at about 2.1 million, comprising roughly 1.4 million excess deaths, 550,000 lost births and under 400,000 net emigration; earlier writers had attributed a far larger share of the population shortfall to migration. The revolution also produced the 1917 constitution, whose Article 27 provided the legal basis for the agrarian redistribution of the following decades.

Parties

The contending armies and factions of the Mexican Revolution, and the federal forces before them, drove civilians from the countryside and across the northern border; the United States admitted large numbers as refugees and briefly interned others

Disputed

The share of Mexico's population shortfall between 1910 and 1930 attributable to deaths as against emigration and lost births was long disputed; McCaa's projections shifted the consensus toward a far higher death figure and a lower migration figure than mid-century accounts had assumed, and the 1921 census is regarded as unreliable.

The denominator

The Porfirian census of 27 October 1910 counted 15,160,369 people. The 1921 census counted 14,334,780, a fall of about 800,000 despite a decade of natural increase; historical demographers attribute the shortfall to war deaths, the 1918 influenza pandemic, lost births and emigration to the United States.

The 400,000 figure is the estimated net migration to the United States and does not include the far larger internal displacement within Mexico, which was never counted.

Where the baseline comes from

Mexican Revolution — Wikipediaopen-edited
Demographics of Mexico — Wikipediaopen-edited

On the death toll

McCaa's inverse projection gives about 1.4 million excess deaths for 1910-1920, within a total demographic cost of 2.1 million including 550,000 lost births. Older estimates of 1 to 2 million 'deaths' often conflated deaths, lost births and emigration. A large share of the excess mortality was caused by the 1918-19 influenza pandemic, whose effects McCaa's method does not fully separate from those of the fighting, which is the principal reason for the range.

Documented forms of violence

Mass KillingSummary ExecutionForced LabourDestruction of Property

Forced conscription, summary executions, requisitioning and the burning of villages by federal and revolutionary forces alike are documented in Mexican military records, contemporary reporting and the scholarship on the Morelos campaign.