Over the last decade, corpus linguistic methods have been increasingly used in interdisciplinary studies of history, social sciences and political science (see Baker and McEnery 2015, Alasuutari et al 2019). By contrast to the approaches traditionally practiced in Critical Discourse Analysis, corpus methods make it possible to identify significant collocations, phraseological patterns and subtle diachronic trends in large collections of texts (see Tyrkkö 2016, Riihimäki accepted). However, although a number of corpora focused on political discourse (e.g., Hansard corpora, CORPS, CoPS, Europarl) are available, they tend to focus on a particular country, a specific political event type or a restricted time period, and consequently they have limited scope for addressing long-term developments of political discourse or comparing regional and register differences (see Ädel 2010, Kytö 2001, Baker 2012, Cheng 2013, Perrez et al. 2018) In this presentation we introduce the Diachronic Corpus of Political Speeches (DCPS), a corpus specifically designed for investigating such questions. The DCPS is an extended and annotated version of the current SCPS (Small Corpus of Political Speeches), a collection of 700 full-length political speeches. Compared to the SCPS, the DCPS will be balanced across the time span (1800-present day) and the key variables, and it will be roughly twice the size of SCPS. The DCPS is representative of political speeches in the UK, the US, Canada and Australia, and also includes samples from other English-speaking countries. The speeches represent a wide range of communicative settings and a wide variety of political actors including unelected civic leaders. Contextual information is included in the detailed metadata, audience responses are included when applicable, and morphosyntactic information is provided through lemmatization and part-of-speech tagging performed with TreeTagger. A discourse-pragmatic annotation will also be included in the form of manually added in-line tags, assessed by regular inter-coder reliability checks. References Ädel, A. (2010). How to use corpus linguistics in the study of political discourse. In A. O'Keeffe and M.J. McCarthy (eds), The Routledge Handbook of Corpus Linguistics. London: Routledge. 591-604. Alasuutari, P., Tyrkkö J., & Rautalin M. (2019). The rise of the idea of model in policymaking: The case of the British parliament, 1803–2005. European Journal of Sociology 59:3. ***–***. Baker, P. (2012). Acceptable bias? Using corpus linguistics methods with critical discourse analysis. Critical Discourse Studies, Vol 9, Issue 3. 247–256. Baker, P. and McEnery, T. (eds.) (2015). Corpora and discourse studies: integrating discourse and corpora. Basingstoke: Palgrave Macmillan. Cheng, W. (2013). “Corpus-based linguistic approaches to critical discourse analysis”. The Encyclopedia of Applied Linguistics, ed. by Carol A. Chapelle, 1–8. Oxford: Wiley-Blackwell. Kytö, M. (2001). Corpora and historical linguistics. RBLA, Belo Horizonte, v. 11, n. 2, p. 417-457, 2011 Guerini, M., Giampiccolo, D., Moretti, G., Sprugnoli, R., & Strapparava, C. (****) The New Release of CORPS: A Corpus of Political Speeches Annotated with Audience Reactions. In Multimodal Communication in Political Speech. Shaping Minds and Social Action (pp. 86-98). Springer Berlin Heidelberg, 2013. Perrez, J., Randour, F. & Reuchamps, M. (2018). On the representativeness of political corpora in linguistic research. Paper presented at AFLiCo JET 2018 “Corpora and Representativeness” 3-4 May 2018, Paris Nanterre University. http://hdl.handle.net/2268/222865 Riihimäki, J. (accepted). At the Heart and in the Margins: Discursive construction of British national identity in relation to the EU in British parliamentary debates from 1973 to 2015. Discourse in Society. Small Corpus of Political Speeches. 2007–. Compiled by Jukka Tyrkkö at the Universities of Helsinki and Tampere with the assistance of Jenni Riihimäki and Veera Saarimäki. http://www.helsinki.fi/varieng/CoRD/corpora/SCPS/ Tyrkkö, J. (2016). Looking for Rhetorical Thresholds: Pronoun Frequencies in Political Speeches. In Nevala Minna, Gabrielle Mazzon, Carla Suhr and Ursula Lutzky (eds.) The Pragmatics and Stylistics of Identity Construction and Characterisation (Studies in Variation, Contacts and Change in English 17). Helsinki: Varieng.