The musical repertoire cultivated in Latin America between the sixteenth and nineteenth centuries has been the focus of important studies and editions from the foundational works by Lange and Stevenson up until today. However, with a few exceptions, this work suffers from two basic problems in the ways it approaches or edits this repertoire: 1) the omission of plainchant, and 2) a lack of attention to its ceremonial background. A third, and not lesser point is that work about colonial music generally does not extend into the independence period, and vice versa, despite the fact that the ecclesiastical organization and liturgical practices did not change when the Spanish colonies became republics. This article addresses these problems by studying practices of liturgical music at the Cathedral of Santiago de Chile from 1721 (when a permanent music chapel was officially established) up to 1840 (the year in which the Santiago was promoted to an archdiocese and was no longer dependent on the metropolitan church of Lima). In order to do so, the authors propose a solution on two levels: on the one hand, we have reconstructed the calendar of feasts on which the music chapel took part, and on the other hand, we have recreated, as an example of the former, the liturgical music performed on Palm Sunday (procession and mass, including the Passion). For such a task, we have studied many primary musical and historical sources, both handwritten and printed, from the period.