The Papal Zouaves were formed in defence of the Papal States. The Zouaves evolved out of a unit formed by Lamoricière in 1860, the Franco-Belgian Tirailleurs. On January 1, 1861 the unit was renamed the Papal Zouaves.
The Zuavi Pontifici were mainly young men, unmarried and Roman Catholic, who volunteered to assist Pope Pius IX in his struggle against the Italian Risorgimento. They wore a similar style of uniform to that of the French Zouaves but in grey with red trim. A grey and red kepi was substituted for the North African fez.
All orders were given in French and the unit was commanded by a Swiss Colonel, M. Allet. Nonetheless, the regiment was truly international, and by May 1868 numbered 4,592 men including 1,910 Dutch, 1,301 French and 686 Belgians. 500 volunteers were raised from Canada. The Irish were to raise a battalion, the Battalion of St. Patrick.
The Papal Zouaves assisted in the notable Franco/Papal victory at the Battle of Mentana on November 3, 1867 suffering the brunt of the fighting, sustaining 81 casualties in the battle, including 24 killed (the Papal forces suffered only 30 dead in total) and 57 wounded, with the official report of the battle prepared by the French commander, General de Failly citing their bravery. They were also mentioned in Victor Hugo's poem Mentana.
The Zouaves also played a role in the final engagements against the forces of the newly united Kingdom of Italy in September 1870, in which the Papal forces were outnumbered almost seven to one. The Zouaves fought bravely before surrender. Several Zouaves were executed or murdered by the Italian forces following the surrender.
The French contingent of the Papal Zouaves regrouped as the Volontaires de l'Ouest (Volunteers of the West) to fight on the French side in the Franco-Prussian War, where they kept their grey and red Papal uniforms. The Zouaves saw action outside Orléans, Patay and the Battle of Loigny. The Volontaires de l'Ouest were disbanded after the entrance of Prussian troops into Paris.
An English veteran, Joseph Powell, published his account of his service with the Papal Zouaves, Two Years in the Pontifical Zouaves
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