The Spanish Constitution of 1978 establishes the non-denominationality of the State, providing that the public authorities take into account the religious beliefs of society, maintaining cooperative relations with the Catholic Church and other confessions.

From the 5th to the 7th century, about thirty synods, were held at Toledo to regulate and standardise matters of discipline, decreed uniformity of liturgy throughout the kingdom.

Spanish missionaries carried Catholicism to the Americas and the Philippines, establishing various missions in the newly colonized lands.

According to Juan Avilés Farré, Catholicism constituted the "doctrinal basis of the most significant organizations of the anti-democratic and anti-liberal right-wing" in Spain developed in the period going from the demise of right-wing liberal conservatism led by Cánovas del Castillo to the installment of the Francoist dictatorship, including maurism, Patriotic Union, the group around Acción Española and Falange Española.

There are also magnificent monasteries like San Millán and Silos in La Rioja, Monstserrat and Poblet in Catalonia, El Escorial and El Paular in Madrid, San Juan de los Reyes in Castile-La Mancha, the Abbey of Santa María la Real de Las Huelgas in Castile and Leon, or churches like Sagrada Família in Barcelona by Antoni Gaudí.

For centuries Holy Week has had a special significance in the church calendar in Spain, where early on Good Friday the darkened streets of dawn become the stage for solemn processions and celebrations that lead up to festivities of Easter Sunday.

[8] For over a thousand years, Europeans living north of the Alps have made their way to the closest place in Europe "where they could access the spiritual authority of an Apostle: Santiago de Compostela".

A huge majority of young Spaniards, including those who self-identify as Catholic, ignore the Church's stance on issues such as pre-marital sex, sexual orientation or contraception.