Albania is a secular and religiously diverse country with no official religion and thus, freedom of religion, belief and conscience are guaranteed under the country's constitution. Islam is the most common religion in Albania, followed by Christianity, though religiosity is low and there are many irreligious Albanians. In the 2023 Census in Albania, Muslims accounted for 50,67 % of the total population, Christians made up around 15,64 %, while irreligious were 17.37%. The other 15.76% were Undeclared.
Religion in Russia is diverse, with Orthodox Christianity being the most widely professed faith, but with significant minorities of non-religious people and adherents of other faiths.
Moldova's constitution provides for freedom of religion and complete separation of church and state, though the constitution cites the "exceptional importance" of Eastern Orthodox Christianity. Discrimination on the basis of religious affiliation is illegal, and incitement to religious and ethnic hatred was made illegal in May 2022. Religion in Moldova is dominated by the Eastern Orthodox branch of Christianity. According to the 2014 Moldovan census, 90 per cent of the country reported to be of the Eastern Orthodox Christian faith. Of this number, around eighty to 90 per cent of Orthodox Moldovans belong to the Moldovan Orthodox Church which is subordinate to the Russian Orthodox Church, and has played a powerful role in deepening Russia's influence in Moldova. The remaining 10–20 per cent of Orthodox Moldovans belong to the Metropolis of Bessarabia, which is subordinate to the Romanian Orthodox Church.
Religion has been a major influence on the societies, cultures, traditions, philosophies, artistic expressions and laws within present-day Europe. The largest religion in Europe is Christianity. However, irreligion and practical secularisation are also prominent in some countries. In Southeastern Europe, three countries have Muslim majorities, with Christianity being the second-largest religion in those countries. Ancient European religions included veneration for deities such as Zeus. Modern revival movements of these religions include Heathenism, Rodnovery, Romuva, Druidry, Wicca, and others. Smaller religions include Indian religions, Judaism, and some East Asian religions, which are found in their largest groups in Britain, France, and Kalmykia.
Evangelical Protestantism is one of five officially recognized faiths in Albania. It is a Christian faith that views Jesus Christ as its founder and head, and the Bible as its written authority.
Serbia has been traditionally a Christian country since the Christianization of Serbs by Clement of Ohrid and Saint Naum in the 9th century. The dominant confession is Eastern Orthodoxy in the fold of Serbian Orthodox Church.
Eastern Orthodox Christianity is largest religion in Montenegro, but there are also sizeable numbers of adherents of both Catholic Christianity and Islam.
Religion in Bulgaria has been dominated by Christianity since its adoption as the state religion in 864. The dominant form of the religion is Eastern Orthodox Christianity within the fold of the Bulgarian Orthodox Church. During the Ottoman rule of the Balkans, Islam spread to the territories of Bulgaria, and it remains a significant minority today. The Catholic Church has roots in the country since the Middle Ages, and Protestantism arrived in the 19th century; both of them remain very small minorities. Today, a significant part of the Bulgarians are not religious, or believers who do not identify with any specific religion, and Bulgaria has been the cradle of some new religions, notably the Neo-Theosophical movement of Dunovism.
Christianity in Kazakhstan is the second most practiced religion after Islam and one of the major religions of Kazakhstan.
Christianity is the predominant religion in Ukraine, with 85% of the population identifying as Christian according to a 2022 survey conducted by the Kyiv International Institute of Sociology (KIIS). Seventy-two percent of the population avowed fidelity to an Eastern Orthodox Church: 54% of Ukrainians proclaimed adherence to the autocephalous Orthodox Church of Ukraine; 14% identified as Orthodox Christian without specifying a church affiliation; 4% associated with the Moscow Patriarchate. Another 9% of Ukrainians professed devotion to the Catholic Church in Ukraine: 8% Ukrainian Greek Catholics and 1% Latin Catholics. Two percent of the population declared affiliation to a mainstream Protestant Church, and a further 2% identified with some alternative sect of Christianity.
After the October Revolution, there was a movement within the Soviet Union to unite all of the people of the world under communist rule known as world communism. Communism as interpreted by Vladimir Lenin and his successors in the Soviet government included the abolition of religion and to this effect the Soviet government launched a long-running unofficial campaign to eliminate religion from society. Since some of these Slavic states tied their ethnic heritage to their ethnic churches, both the peoples and their churches were targeted by the Soviets.
The dominant religion in Slovenia is Christianity, primarily the Catholic Church, which is the largest Christian denomination in the country. Other Christian groups having significant followings in the country include Eastern Orthodoxy and Protestantism (Lutheranism). Islam, Judaism and Hinduism are small minorities in Slovenia. About 18% of the population are either agnostic or atheist.
The predominant religion in the Republic of Ireland is Christianity, with the largest denomination being the Catholic Church. The Constitution of Ireland says that the state may not endorse any particular religion and guarantees freedom of religion.
Christianity in Uzbekistan is a minority religion.
Religion in Kosovo is separated from the state. The Constitution establishes Kosovo as a secular state that is neutral in matters of religious beliefs and where everyone is equal before the law and freedom to belief, conscience and religion is guaranteed.
In North Macedonia, the most common religion is Eastern Orthodox Christianity, practiced mainly by ethnic Macedonians, Serbians, Vlachs, and Romanis. The vast majority of the Eastern Orthodox in the country belong to the Macedonian Orthodox Church, which declared autocephaly from the Serbian Orthodox Church in 1967.
Christianity is the most widely professed religion in Croatia, representing 87.4% of the total population. A large majority of the Croats declare themselves to be members of the Catholic Church.
Estonia, historically a Lutheran Christian nation, is today one of the least religious countries in the world in terms of declared attitudes, with only 14 percent of the population declaring religion to be an important part of their daily life. This is thought to largely be a result of the Soviet occupation of Estonia in 1940, prior to which Estonia had a large Christian majority.
Eastern Orthodoxy arrived in the areas of Illyrii proprie dicti or Principality of Arbanon during the period of Byzantine Empire. Those areas fell under the Ottoman Empire during the late medieval times and Eastern Orthodoxy underwent deep sociopolitical difficulties that lasted until the fall of the Ottoman Empire. Between 1913 and until the start of WWII under the newly recognized state of Albania, Eastern Orthodoxy saw a revival and in the 1937 the Autocephaly after a short Eastern Orthodoxy schism and contestation was recognized. Decades of persecution under the Communist state atheism, which started in 1967 and officially ended in December 1990, greatly weakened all religions and their practices especially Christians of Albania. The post-communist period and the lifting of legal and other government restrictions on religion allowed Orthodoxy to revive through institutions and enabled the development of new infrastructure, literature, educational facilities, international transnational links and other social activities.
The main religion traditionally practiced in Latvia is Christianity. As of 2019, it is the largest religion (68.84%), though only about 7% of the population attends religious services regularly.
