This article studies the disentailment of mortmain in Colombia. Most of this land was held by the Catholic Church, which derived considerable economic and political power from its ownership. The Radical faction of the Liberal Party, which governed the country between 1863 and 1876, promoted numerous reforms directed at eliminating the institutions that had survived the years of Spanish colonial rule, and were an obstacle to the advance of the economy. A substantial portion of all the properties of the Church were thus expropriated. This process was culminated with the signing of a treaTY –“Concordato”– between the Colombian government and Holy See. The treaTY recognized in favor of the Church “the value of disentailed loans and property”. Colombian historiography has given little attention to the process of disentailment, as a result of the influence of the Conservative historiography, which portrayed it as a failure. This mistaken appreciation can only be corrected through research in primary sources. In this paper we have used primary sources that had not been discussed in the most influential works on Colombian economic history of the 19th century and conclude that it was the main economic reform of that period, since it represented at least 16% of the GDP of 1860 and was a very profitable operation for the government.