Estonian politics during the 1920s was dominated by unstable coalition governments, with a government lasting on average a period of 11 months. This was due to the large number of political parties holding seats in the Riigikogu, which often resulted in discord on specific issues. The 1920s also saw the development of national culture, with emphasis on Estonian language, history, education and ethnography. National minorities were granted cultural autonomy. Communism persisted as a threat to stability in the early 1920s but receded after a failed December 1924 Estonian coup d'état attempt. A volunteer Estonian Defence League as subsequently established. However efforts to establish a Baltic League comprising the Baltic states, Finland and Poland, failed to materialise.