The diezmo was a compulsory ecclesiastical tithe collected in Spain and its empire from the Middle Ages until the reign of Isabel II in the mid-19th century.
[2] Ferdinand III of Castile proposed to Pope Innocent IV the possibility that the royal treasury would receive the third of the diezmo destined for the construction of churches, in order to pay the costs of the siege of Seville.
[1] The diezmo was greatly reduced during the Trienio liberal of 1821–1823 (a decree of 29 June 1821 cut it by half) but restored in full force by the absolutist government that followed.
[5] In the American portions of the Spanish Empire, the diezmo was collected directly by civil functionaries for the Crown, on the condition that they would erect, subsidize, and maintain churches.
This tax constituted roughly ten percent of the Spanish Crown's income and was collected from owners of ranches and rural buildings.
In general, the Indians who made up the vast majority of the population in colonial Spanish America were exempted from paying tithes on such native crops as maize and potatoes that they raised for their own subsistence.
[citation needed] When various Latin American countries gained their independence from Spain in the 19th century, their governments took over the tax, which was considered an abuse by the Creole landowners.