The thesis concentrates on Latin influence on North Germanic languages, especially on Norwegian. First part deals with this topic from sociolinguistic point of view: relationship between Latin and domestic languages in Middle Ages, discerning contexts, where Latin was used, emphasizing the role of church, schools and literature. Second part concentrates on concrete examples of Latin influence, persisting to the modern times, especially loanwords, prefixes and suffixes, irregular declension, idioms. Original research concentrates on Norwegian letters from Middle Age, in Diplomatarium Norwegicum. Research about numbers of Latin letters and letters in domestic language, according to topic and time, in comparison with similar informations from Denmark and Sweden