The Republican government which came to power in Spain in 1931 was strongly anti-Catholic, secularising education, prohibiting religious education in the schools, and expelling the Jesuits from the country. The Spanish Constitution of 1931 was marked by what Catholics considered a deprivation of their rights. By law, the Church's properties became the property of the state, and the Church had to pay the state rent and taxes in order to continue its use of these properties. In the pope's words: "Thus the Catholic Church is compelled to pay taxes on what was violently wrenched from her". The encyclical also denounced the fact that religious vestments, liturgical instruments, statues, pictures, vases, gems and similar objects necessary for worship were expropriated as well. It condemned the expropriation of all private Catholic schools from religious orders in order to reopen them as secular schools.
Pope Pius XI, whose church faced similar persecutions in the USSR and Mexico, called on Spanish Catholics to defend themselves against the persecution with all legal means. He had previously condemned similar destructive forces in the encyclical Quas primas in 1925.
The encyclical pointed to greed as a motivation for the theft of the Church's artistic treasures and indicated that the government showed no regard for the dignity of country's faithful and their attachment to these religious works of art.
Although the government was heavily criticised, the Pope noted: "Universally known is the fact that the Catholic Church is never bound to one form of government more than to another, provided the Divine rights of God and of Christian consciences are safe". The encyclical called the acts of the Spanish government an "offence not only to Religion and the Church, but also to those declared principles of civil liberty on which the new Spanish regime declares it bases itself".