The object of this dissertation is the range, distribution, and usage of words imported from Middle Low German in medieval charters originating from the Swedish province of Närke. The charters are all written in Old Swedish between the years 1350 and 1520. The study reveals that some examples of certain imported words display traits of being foreign words (Germ. Fremdwörter), although they in many cases have existed in Old Swedish for quite some time in more orthographically and morphologically integrated forms. The forms in question are most frequent in charters issued in the early 16th century, primarily in the office of Örebro castle. The occurrence of imported words containing the three prefixes be-, for(e)- and vidher- can be located mainly to three areas in Närke: the town of Örebro, the convent of Riseberga, and the south-east of the province. Some manifestations of the prefix be- can be traced back to Middle Low German written forms. The amount and diversity of the imported words used in the different formulas which charters are composed of are discussed. The formulas which constitute the main body of the texts and the core of their content are found to display the largest quantity and variety of imported words. The frequency of the imported words is also studied from social, regional and chronological perspectives respectively. The charters issued by the burghers of Örebro and the miners of Noraskogen are found to be richest in imported words, followed by texts issued by members of the nobility. Regarding the regional comparison, the charters originating from the northern parts of Närke, where the town of Örebro and the Noraskogen mining district are located, and from the south-east of the province contain the largest amount of imported words. The chronological comparison shows that both the number and the frequency of the imported words increase over time. Språk i boken: svenska