The spike in the number of self-declared "Muslims" during socialist Yugoslavia times should thus be understood as persons having a family Muslim cultural background (similar to the concept of cultural Christians), rather than practicing believers in Islam. Based on the figures recorded during the 1931 to 1961 census, it may also be concluded that a certain number of Muslim believers declared themselves as Croats or Yugoslavs. After the dissolution of Yugoslavia, an additional increase can be attributed to the influx of Bosnian Muslims that took place during and after the 1992-1996 Bosnian conflict. The 2001 Croatian census identified a total of 56,777 adherents of Islam, or 1.3% of the total population of Croatia. The following ethnic groups were presumed to be significantly Muslim:  The published data from the 2011 Croatian census included a crosstab of ethnicity and religion which showed that a total of 62,977 Muslims (1.47% of the total population) was divided between the following ethnic groups:  Croatia's capital Zagreb has one of the biggest mosques in Europe since 1987. During the existence of the Ottoman Empire it had none because Zagreb, as well as most parts of Croatia, was not occupied by the Ottomans during the Hundred Years' Croatian–Ottoman War. The Bosniak imam Ševko Omerbašić, was the long-time leader of the Muslim community of Croatia and the Mufti of Zagreb. A new mosque in Rijeka was opened in May 2013. The Muslim community is also planning to build a mosque in Osijek and Sisak. A mosque in Karlovac is also being considered.