Europeans were friars and priests who were interested in trying to convert the natives to Christianity. They translated Catholic catechisms and confessional manuals and acquired a good grasp of the indigenous languages and often even composed grammars and dictionaries of the indigenous languages. These early grammars of native languages systematized the reading and writing of indigenous languages in their own time and help us understand them today. The most widely known early grammars and dictionaries are of the Aztec language, Nahuatl. Famous examples are the works written by Alonso de Molina and Andrés de Olmos. But also Mayan and other Mesoamerican languages have early grammars and dictionaries, some of very high quality. The introduction of the Latin alphabet and the elaboration of conventions for writing indigenous languages allowed for the subsequent creation of a wide range of texts. And indigenous writers took advantage of the new techniques to document their own history and tradition in the new writing, while monks kept on extending literacy in the indigenous population. This tradition lasted only a few centuries however and due to royal decrees about Spanish being the only language of the Spanish empire by the mid-1700s most indigenous languages were left without a living tradition for writing. Oral literature, however, kept being transmitted to this day in many indigenous languages and began to be collected by ethnologists in the beginnings of the 20th century, however without promoting native language literacy in the communities in which they worked. It is an important and extremely difficult job in the Mesoamerica of today, and what that is only beginning to be undertaken, to return native language literacy to the indigenous peoples. But during the first post-conquest centuries a large number of texts in indigenous Mesoamerican languages were generated. Codices of major importance Codex Mendoza Florentine Codex. A twelve-volume work composed under the direction of Franciscan friar Bernardino de Sahagún and sent to Europe in 1576. Separate books deal with Aztec religion, divinatory practices; lords and rulers; elite long-distance merchants pochteca; commoners; the "earthly things" including a compendium of information on flora and fauna; rocks and soil types. Volume 12 is a history of the conquest from the Tenochtitlan-Tlatelolco viewpoint. It is called the "Florentine Codex" because it was found in a library in Florence, Italy. Historical accounts Many of the post-conquest texts are historical accounts, either in the form of annals recounting year by year