Steingrímsson, SteinþórSigurðsson, Einar FreyrJasonarson, AtliJohansson, RichardStymne, Sara2025-02-192025-02-192025-03https://hdl.handle.net/10062/107261We present MC-19, a new Icelandic historical corpus containing texts from the period 1800-1920. We describe approaches for enhancing a corpus of historical texts, by preparing the texts so that they can be processed using state-of-the-art NLP tools. We train encoder-decoder models to reduce the number of OCR errors while leaving other orthographical variation be. We generate a separate modern spelling layer by normalizing the spelling to comply with modern spelling rules, using a statistical modernization ruleset as well as a dictionary of the most common words. This allows for the texts to be PoS-tagged and lemmatized using available tools, facilitating usage of the corpus for researchers and language technologists. The published version of the corpus contains over 270 million tokens.enAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttps://creativecommons.org/licenses/by-nc-nd/4.0/Article