The September Convention was a treaty, signed on 15 September 1864, between the Kingdom of Italy and the French Empire, under which: French Emperor Napoleon III would withdraw all French troops from Rome within two years. King Victor Emmanuel II of Italy guaranteed the frontiers of the Papal States, which at the time consisted of Rome and Latium. Additionally, in a protocol at first kept secret, the Italian government pledged to move its capital from Turin to another city (later selected by a commission to be Florence) within six months, to prove its good faith in giving up all claims on Rome. Background Benito Juárez was elected President of Mexico in 1861. In the aftermath of the Reform War (1858-1860), the country was left with a severely damaged infrastructure, crippled economy, and massive debt. Juárez not only continued the anti-clerical policies of the liberals, but, more importantly, canceled repayments of interest on foreign loans that had been taken out by the defeated conservatives. The establishment of a friendly monarchy in Mexico would ensure European access to Latin American markets; and French access to Mexican silver. To realize his ambitions without other European interference, Napoleon III entered into a coalition with Britain and Spain, while the U.S. was occupied with the American Civil War (1861–65), and unable to enforce the Monroe Doctrine. Spain, Britain and France, angry over unpaid Mexican debts, sent a joint expeditionary force that seized the Veracruz Customs House in December 1861. Spain and Britain soon withdrew after they realized that the French Emperor Napoleon III intended to overthrow the Juárez government and establish a Second Mexican Empire, with the support of the remnants of the Conservative side in the Reform War. The significant investment of men and materiel gave Napoleon III a reason to reduce military commitments elsewhere, a reason that he expected would be acceptable to the French people. Treaty According to the terms of the treaty, Napoleon III would withdraw all French troops from Rome within two years; and King Victor Emmanuel II of Italy would guarantee the territorial integrity of the Papal States. This treaty was opposed by the Pope, the French Catholics, and by Italian patriots. When the government’s move to Florence was announced, it caused widespread rioting in Turin, whose repression caused 55 dead and at least 133 wounded among the protesters; however, the King and the Italian government were duly transferred