Convened by Pope Pius IX inside St. Peter's Basilica in Rome, Italy, the First Vatican Council was cut short in 1870 due to the outbreak of the Franco-Prussian War and the capturing of Rome by Italian nationalist forces. Before its abrupt adjournment, the council issued the landmark dogmatic constitution 'Pastor aeternus', which formally defined the dogma of Papal Infallibility. This decree stated that when the Pope speaks 'ex cathedra' on matters of faith or morals, his definitions are preserved from error, greatly strengthening central papal authority during a time of intense European secularization.

This dramatic assertion of absolute spiritual authority deepened a widening cultural divide between secular and religious writers across Europe. It forced Catholic poets to grapple with themes of absolute obedience, leading to highly defensive, intensely devotional art, while inspiring anti-clerical verse among secular poets.