One of the most momentous events in the history of the Slavic peoples was the ninth-century creation by Constantine, his brother Methodius, and their disciples of two alphabets: Cyrillic and Glagolitic. Details about who invented which alphabet are hazy but the motivation for this great achievement is clear: the translation of Greek texts of the New Testament into the new Slavic letters for missionary work among the Slavs of Greater Moravia and then in other parts of the Slavic world. The early stage of this new written language, represented by a group of homogeneous Cyrillic and Glagolitic manuscripts, is called Old Church Slavic; a later stage exhibiting regional divergence in language sounds and forms is named Church Slavic. The two alphabets were used in the territories of the Croats and the Serbs, Cyrillic consistently by the Serbs, while the Croats preferred Glagolitic and vernacular alphabets based on Latin letters. The nineteenth and twentieth centuries witnessed the development of Croatian and Serbian nationalistic movements that invariably aected language and alphabet usage, in some cases maintaining digraphia and in others favoring monographia.