Capture of Rome and the End of Papal Temporal Power (1867–1870)

1. Italy and France sign the September Convention

   Sep 15, 1864Labels: September Convention, France, Kingdom of

   Italy and France signed an agreement meant to calm the "Roman Question"—the unresolved issue of Rome remaining under papal rule while most of Italy had unified. France promised to withdraw its troops from Rome within two years, and Italy promised to respect the remaining Papal States’ borders. Italy also agreed (in a related protocol) to move its capital away from Turin, signaling it would pause direct pressure on Rome.

   • September Convention
   • Britannica Rome

2. Italian capital shifts from Turin to Florence

   Jan 1, 1865Labels: Florence, Turin, Kingdom of

   After the September Convention, Italy moved its seat of government from Turin to Florence, a step meant to show good faith that Rome would not be seized immediately. The move also sparked anger in Turin, where many saw it as giving in to French pressure connected to protecting the pope’s territory. This relocation helped set the political backdrop for later attempts to take Rome.

   • September Convention
   • Turin Massacre

3. French troops leave Rome under the Convention

   Dec 1, 1866Labels: French garrison, Pope Pius, Rome

   France withdrew its garrison from Rome, which had been a key military support for Pope Pius IX. Although French forces would later return, this withdrawal showed how dependent papal rule in Rome was on outside protection. It also encouraged Italian nationalists who believed Rome could eventually be brought into the Kingdom of Italy.

   • September Convention
   • Britannica Rome

4. Garibaldi launches a new campaign toward Rome

   Oct 1, 1867Labels: Giuseppe Garibaldi, Volunteer Corps, Rome campaign

   In 1867, Giuseppe Garibaldi organized volunteers to try again to bring Rome into Italy, aiming to finish unification. The Italian government, worried about provoking France and international backlash, tried to restrain him, but the movement gathered momentum in central Italy. This set up a direct clash between volunteer nationalists and papal forces backed by France.

   • Britannica Rome
   • Mentana

5. Franco-Papal victory at the Battle of Mentana

   Nov 3, 1867Labels: Battle of, French troops, Papal forces

   French and papal troops defeated Garibaldi’s volunteers near Mentana, stopping the 1867 attempt to take Rome. The battle confirmed that Rome could not be captured while France was willing and able to intervene militarily. It also underlined how the fate of Rome was tied to wider European politics, not only Italian decisions.

   • Mentana
   • September Convention

6. Franco-Prussian War forces French attention away from Rome

   Jul 19, 1870Labels: Franco-Prussian War, France, Prussia

   War broke out between France and Prussia, drawing French troops and resources away from other commitments. As France became increasingly threatened at home, it was less able to keep a protective presence around Rome. This shift created the opening that Italian leaders had waited for since earlier failures in 1862 and 1867.

   • September Convention
   • Britannica Rome

7. French garrison withdrawn from Rome during the war

   Aug 1, 1870Labels: French garrison, Rome, Pope Pius

   With the Franco-Prussian War underway, the French garrison that helped protect Pope Pius IX was withdrawn. This removal changed the balance of power around Rome and made a direct Italian move much more feasible. Italian leaders could now act with far less risk of fighting France on Italian soil.

   • September Convention
   • Britannica Rome

8. Victor Emmanuel II proposes a protected entry into Rome

   Sep 8, 1870Labels: Victor Emmanuel, Pope Pius, Protected entry

   King Victor Emmanuel II sent Pope Pius IX a letter offering to send Italian troops into papal territory while claiming to protect the pope and public order. The proposal asked that the papal army stand down and accept Italy’s presence, which would effectively end papal temporal rule. Pius IX rejected the idea, making a military confrontation more likely.

   • Vatican Savoyard
   • Britannica Rome

9. Italy declares war and marches into papal territory

   Sep 10, 1870Labels: Kingdom of, Papal States, Italian Army

   Italy declared war on the Papal States and the Italian army crossed the frontier the next day, advancing toward Rome. The Italian leadership moved carefully, still hoping for a negotiated entry that would reduce bloodshed and political fallout. Pius IX nevertheless ordered resistance to show that Rome was being taken by force, not handed over voluntarily.

   • Vatican Savoyard
   • Capture of Rome

10. Breach of Porta Pia and capture of Rome

    Sep 20, 1870Labels: Porta Pia, Aurelian Walls, Capture of

    Italian troops attacked Rome’s Aurelian Walls and opened a breach near Porta Pia, entering the city on September 20. The fighting was limited but symbolic, marking the end of the Papal States as a territorial power. With Rome taken, the last major political obstacle to Italian unification was removed.

    • Britannica Rome
    • Capture of Rome

11. Plebiscite votes to annex Rome and Lazio to Italy

    Oct 2, 1870Labels: Plebiscite, Lazio, Kingdom of

    A plebiscite (popular vote) was held in Rome and surrounding Lazio to approve joining the Kingdom of Italy. The result heavily favored annexation, giving the new government a legal and political claim that it represented the people’s will. The Vatican rejected the process, but the vote helped Italy present the takeover as national unification rather than simple conquest.

    • Capture of Rome
    • Reference org

12. Rome formally becomes Italy’s capital

    Feb 3, 1871Labels: Rome, Capital of, Pope Pius

    Rome was officially designated the capital of the Kingdom of Italy, completing the political goal of making the historic city the center of the new state. The papacy, however, did not accept the loss of temporal power; Pius IX refused Italy’s settlement offers and claimed to be a "prisoner" in the Vatican. The conflict over sovereignty and church–state relations became known as the Roman Question.

    • Britannica Rome
    • Capture of Rome

13. Italy passes the Law of Guarantees

    May 13, 1871Labels: Law of, Kingdom of, Pope Pius

    Italy adopted the Law of Guarantees to define the pope’s rights and protections after the loss of papal territory. The law recognized the pope’s special status, offered financial support, and granted use of key papal palaces, aiming to protect the Church’s spiritual independence within an Italian Rome. Pius IX rejected the law because it came from the Italian state and could be changed by it, leaving the dispute unresolved for decades.

    • Britannica Guarantees
    • Law of Guarantees