In 1863 Napoleon III received a letter from an adviser outlining a terrifying future. The population of the United States was 32 million; by 1963, the adviser warned, with a suspiciously exact figure, it would reach 512 million. Washington would need more land, annexing Mexico and then Latin America. In 100 years the US ‘would be capable of trying to enslave the universe’. The adviser then congratulated Napoleon on the ‘boldest’ idea of ‘modern times’: stopping US global hegemony.

The French emperor’s plan was indeed bold. With the US consumed by civil war, Napoleon invaded Mexico. In 1862 he sent 30,000 troops to overthrow the democratic republic and replace it with a French-backed monarchy.  The Second Mexican Empire, as this regime is known, would act as a barrier to US expansion.

As Raymond Jonas brilliantly demonstrates in Habsburgs on the Rio Grande, it was not only French resources that were mobilised; it was a transnational effort drawing on manpower from across Europe, the Americas, even North Africa. As one Quebecois volunteer noted, among the troops were ‘German noblemen, English merchants, Polish and Hungarian refugees – every kind of hero in search of his novel’.

Yet despite the power behind it, the Empire proved ephemeral. In Jonas’ view, this was in part because it was ‘founded on a lie’ – that the people of Mexico would welcome a European monarch. This lie originated with members of the Mexican Conservative Party who wished to overturn secular reforms introduced by the Liberals in the 1850s. Conservatives appealed to Europe for help, describing an oppressed silent Catholic majority that would readily welcome a European royal as ruler. For Napoleon, this was the opportunity he had been waiting for. All he needed was a monarch.

Enter Maximilian, younger brother of Habsburg emperor Franz Joseph. Convinced it was his destiny to rule, the lure of glory across the Atlantic outweighed the warnings he received against taking the throne. His wife, Charlotte, was keen for a political role, too. As Jonas writes, long before officially accepting the crown ‘not only had they settled upon a uniform for their court valets, they had placed an order for the outfits with a firm in Brussels’.

It was the Conservatives, having done much to create the Empire, who undermined Maximilian and Charlotte when they reached Mexico in May 1864. Jonas identifies the archbishop of Mexico as their ‘deadliest opponent’. Napoleon and Maximilian wanted a liberal government in Mexico in line with what they called the ‘spirit of the century’. Told this, the archbishop replied that ‘Mexico has nothing more of the century than the date, that is all’, and ordered his clergy to oppose the Empire. As the fragile edifice of Maximilian’s kingdom crumbled, the imperial couple indulged in magical thinking. Meanwhile, Mexico burned.

Benito Juárez, the deposed president, had never surrendered to the French, who employed tactics of warfare honed in Algeria. Advances seemed impressive, but French forces resembled a ship gliding through the water, leaving behind no trace of its voyage. In its wake, Juárez’s men took back control. Worse was to come. Far from checking US power, the French intervention merely afforded Napoleon an opportunity to witness it firsthand. After defeating the Confederacy, the US threatened France with serious consequences unless its troops left Mexico. In January 1866, Napoleon announced a phased withdrawal. Hearing this, Maximilian decided to return to Europe. Charlotte was furious. Abdicating, she said, was for ‘old men and idiots’. She then travelled to Paris to change the French emperor’s mind. She failed.

Charlotte had one last hope: persuade the pope to sign a concordat that would sanction Maximilian’s secular reforms and bring Catholic Mexico behind the Empire. After two meetings with the pope, Charlotte arrived at the Vatican early one morning unannounced. She suffered a breakdown and accused Napoleon of hiring assassins to poison her.

When Maximilian heard the news he decided, again, to abdicate; however, his usual vacillation gave the Conservatives an opportunity. They worked to persuade him to embrace their clerical vision. While his cabinet met to vote on whether the Empire should continue, Maximilian went butterfly hunting. Unsurprisingly, his supporters insisted he stay; Maximilian agreed.

He hoped that with the hated French gone and the Church behind him, the people would rally. In February 1867 he set out from his capital with 1,500 soldiers, many press-ganged off the streets. This force made it to Querétaro, 130 miles from Mexico City, where it met with his dwindling supporters, but they were soon besieged. Hunger, desertion and disintegration resulted in surrender to Juárez’s forces. Arrested and sentenced to death, Maximilian was executed on 19 June 1867. A Habsburg archduke lay dying in the Mexican dust.

Jonas superbly places the Second Empire in its transnational context. There is less focus, however, on Mexican politics. Monarchy may not have been popular in Mexico, but conservatism was a mass movement – Jonas only provides glimpses of the broader coalition that made the Empire possible, if always improbable. Beyond clerical reactionaries, there is little sense of why other Mexicans, including many Liberals, considered a French-backed Austrian a cause worth dying for.

There is a clue to their motivations in Jonas’ epilogue, where he draws comparisons between Maximilian’s Empire and the authoritarian regime of Porfirio Díaz, who established Mexico’s most stable 19th-century government from 1876 until 1911. Díaz, one of Juárez’s erstwhile generals, may have fought against the Empire, but he and his supporters would surely have agreed with Napoleon’s advice to Maximilian: ‘What is needed in Mexico is a liberal dictatorship.’

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  Habsburgs on the Rio Grande: The Rise and Fall of the Second Mexican Empire
  Raymond Jonas
  Harvard University Press, 384pp, £29.95
  Buy from bookshop.org (affiliate link)

  
  

Edward Shawcross is the author of The Last Emperor of Mexico: A Disaster in the New World (Faber, 2022).