In one of the stranger wars of modern times, the Second French Empire landed its troops in Mexico in 1861 — which was the beginning of a bloody war that would drag on for another six years.
The high point for the French came in the summer of 1863, when they managed to capture the capital and install their own regime.
Though heavy guerrilla resistance and events elsewhere would ultimately lead to their defeat, it is an interesting counterfactual to contemplate how history might have turned out differently if the US had had a powerful European-backed Empire on its southern border.
The road to the war
The cause of the war seems strangely trivial to modern readers. As independent ex-colonies like Mexico grew more economically important throughout the 19th century, the world’s great powers in Europe began to invest in their development.
The accession of Benito Juarez — a brilliant nationalistic politician of indigenous descent — changed this in 1858, as he began to suspend all interest payments to Mexico’s foreign creditors.
The three countries most affected by this – France, Britain and Mexico’s old master Spain – were outraged, and in October 1861 they agreed to a joint intervention at the Treaty of London, where they would invade Veracruz in the south-east of the country in order to put pressure on Juarez.
Coordinating the campaign was remarkably swift, with all three country’s fleets arriving in mid-December and advancing without meeting much resistance until they had reached their agreed destinations at the border of the coastal state of Veracruz.
Napoleon III, Emperor of France, had more ambitious aims, however, and ignored the terms of the treaty by advancing to take the city of Campeche by seaborne assault, before consolidating this new gain with an army.
Realising that it was their partner’s ambition to conquer all of Mexico, and disturbed by both the greed and naked expansionism of this design, the British and Spanish left Mexico and the coalition in April 1862, leaving the French on their own.
The French rationale
There are probably several reasons for this imperialistic French attack. Firstly, much of Napoleon’s popularity and credibility came from his emulation of his famous great-uncle Napoleon I, and he probably believed that such a bold assault on Mexico would secure this for him.
Secondly, there was the issue of international politics. By creating a European Catholic Empire in the region, French ties with the Catholic Hapsburg Empire, which she had been at war with as recently as 1859, would grow stronger in a time of shifting power structures in Europe with Bismarck’s Prussia growing ever-stronger.
In addition, the French were suspicious of the growth and power of the United States in the North, which they saw as an extension of their rival empire Britain’s liberal Protestantism.
By creating a continental European power on America’s doorstep, they could challenge its supremacy over the continent. It was also a good time to get involved, with the US locked in a destructive civil war.
Thirdly and finally, Mexico’s natural resources and mines had massively enriched the Spanish Empire centuries earlier, and Napoleon had decided that it was time for the French to receive the same treatment.
The start of the war
The first major battle of the war – however – ended in crushing defeat. In an event still celebrated in Mexico as Cinco de Mayo day, Napoleon’s forces were defeated at the battle of Puebla, and forced to retreat back to the state of Veracruz.
After receiving reinforcements in October, however, they were able to regain the initiative, with the major cities of Veracruz and Puebla still uncaptured.
In April 1863 the most famous French action of the war took place, when a patrol of 65 men of the French Foreign Legion was attacked and besieged by a force of 3000 Mexicans in a hacienda, where the one-handed Captain Danjou fought with his men to the last, culminating in a suicidal bayonet charge.
By the end of the Spring, the tide of the war had swung in their favour, with a force sent to relieve Puebla defeated at San Lorenzo, and both the besieged cities falling into French hands. Alarmed, Juarez and his cabinet fled north to Chihuahua, where they would remain a government-in-exile until 1867.
With their armies defeated and their government fled, the citizens of Mexico City had little choice but to surrender when the victorious French troops arrived in June.
A Mexican puppet – General Almonte – was installed as President, but Napoleon clearly decided that this in itself was not enough, for the following month the country was declared to be a Catholic Empire.
With many of Mexico’s citizens and conservative governing classes deeply religious, Maximilian – a member of the Catholic Hapsburg family – was invited to become the first Emperor of Mexico.
Maximilian was actually something of a liberal and deeply unsure about the whole business, but under pressure from Napoleon he had little choice but to accept the crown in October.
French military successes continued throughout 1864, as their superior navy and infantry bullied the Mexicans into submission – and many Mexicans took up the Imperial cause against Juarez’s supporters.
The following year, however, things began to unravel for the French. Maximilian’s well-meaning attempts to introduce a liberal constitutional monarchy were unpopular with the mostly Conservative Imperialists, while no liberal would accept the idea of a monarchy.
The American Civil War, meanwhile, was drawing to a close, and the victorious President Lincoln was not happy about the idea of a French puppet monarchy on his doorstep.
With his support for the Republicans – by force if necessary – now clear, Napoleon began to consider the wisdom of pouring more troops into Mexico.
By 1866 Europe was in crisis with Prussia fighting a major war against the Hapsburg Empire, and the French Emperor faced a stark choice between war with the resurgent United States or withdrawing his troops from Mexico.
Sensibly, he chose the latter, and without French backing the Imperialist Mexicans — who were still fighting against Jaurez’s Republicans — suffered defeat after crushing defeat.
Napoleon urged Maximilian to flee, but the brave if hapless Emperor of Mexico — the first and the last — stayed until Juarez had him executed in June 1867, which brought the strange war for Mexico to a close.
Mexico’s Conservative party was discredited for supporting Maximilian, effectively leaving Juarez’s Liberal party in a one-party state.
It was also a political and military disaster for Napoleon, who would be deposed after defeat by the Prussian Empire in 1870.