公元813年的第三次圖爾會議要求神父使用地方語言傳道,即rustica lingua romanica(通俗拉丁語)或日耳曼地方語言,因為當時的百姓已經無法理解規範拉丁語。在一代人的時間內,便產生了查理曼的孫子禿頭查理和日耳曼人路易之間的《斯特拉斯堡誓言》(公元842年),它使用了一種已經不同於拉丁語的語言。見下文選段:
Pro Deo amur et pro christian poblo et nostro commun salvament, d'ist di in avant, in quant Deus savir et podir me dunat, si salvarai eo cist meon fradre Karlo et in ajudha et in cadhuna cosa, si cum om per dreit son fradra salvar dift, in o quid il me altresi fazet, et ab Ludher nul plaid numquam prindrai, qui, meon vol, cist meon fradre Karle in damno sit.
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關於羅曼語族其他語種
法語
Kibler, William W. An Introduction to Old French. New York: Modern Language Association of America. 1984.
Pharies, David A. A Brief History of the Spanish Language. Chicago: University of Chicago Press. 2007.
Pountain, Christopher J. A History of the Spanish Language Through Texts. London: Routledge. 2000.
葡萄牙語
Williams, Edwin B. From Latin to Portuguese: Historical Phonology and Morphology of the Portuguese Language. Philadelphia: University of Pennsylvania Press. 1968.
Batzarov, Zdravko. Orbis Latinus. 2000 [19 September 2009]. (原始內容存檔於2016-03-03).
Norberg, Dag; Johnson, R.H. (Translator). Latin at the End of the Imperial Age. Manuel pratique de latin médiéval. New York: Columbia University Press, Orbis Latinus. 2009 [1980] [2016-02-06]. (原始內容存檔於2007-10-05).
Corpus Grammaticorum Latinorum. Paris: Laboratoire d'Histoire des théories linguistiques. 2008 [19 September 2009]. (原始內容存檔於2009-04-04).