Not only was it asserted that the papacy has a divine right to participate in the government of all countries, coordinately with their temporal authorities, but that the supremacy of Rome in this matter must be recognized; and that in any question between them the temporal authority must conform itself to her order.
And, since the endangering of her position had been mainly brought about by the progress of science, she presumed to define its boundaries, and prescribe limits to its authority.

Still more, she undertook to denounce modern civilization.
These measures were contemplated soon after the return of his Holiness from Gaeta in 1848, and were undertaken by the advice of the Jesuits, who, lingering in the hope that God would work the impossible, supposed that the papacy, in its old age, might be reinvigorated.

The organ of the Curia proclaimed the absolute independence of the Church as regards the state; the dependence of the bishops on the pope; of the diocesan clergy on the bishops; the obligation of the Protestants to abandon their atheism, and return to the fold; the absolute condemnation of all kinds of toleration.

In December, 1854, in an assembly of bishops, the pope had proclaimed the dogma of the immaculate conception.

Ten years subsequently he put forth the celebrated Encyclical Letter and the Syllabus.
The Encyclical Letter is dated December 8, 1864.