Dalam sejarahnya, Estonia merupakan negara ProtestanLutheran,[3][4][5] tetapi kini merupakan salah satu negara paling tidak beragama di dunia dan hanya 14% warga yang menyatakan agama sebagai hal penting dalam kehidupan mereka.[6]
Dari antara mereka yang beragama, sebagian besar menganut agama Kristen. Terdapat paling tidak 90 denominasi Kristen yang diikuti, dan yang paling penting adalah Kristen Ortodoks dan Lutheranisme.[7] Menurut Ringo Ringvee, "agama tidak pernah memainkan peranan yang penting dalam medan tempur politik atau ideologis", sementara "kecenderungan hubungan erat antara negara dengan gereja Lutheran pada akhir tahun 1930-an diakhiri oleh pendudukan Soviet pada tahun 1940". Ia juga menyatakan bahwa "ikatan tradisi agama di sebagian besar keluarga terputus" akibat kebijakan ateisme negaraUni Soviet.[4][8] Sebelum Perang Dunia II, 80% penduduk Estonia tercatat menganut agama Protestan.
Ortodoks Timur telah menggantikan Lutheranisme sebagai denominasi Kristen terbesar di Estonia antara sensus tahun 2001 hingga 2011 karena semakin banyak orang Estonia yang tidak beragama. Lutheranisme masih menjadi agama yang paling populer di antara orang Estonia yang beragama (11% beragama Lutheran), sementara agama Ortodoks Timur kebanyakan dianut oleh minoritas Slavia (sekitar 45% beragama Ortodoks). Menurut hasil penelitian Universitas Tartu, orang Estonia yang tidak beragama belum tentu ateis; malahan pada tahun 2010-an jumlah penganut kepercayaan Neopagan, Buddhisme dan Hindu bertambah di antara mereka yang menyatakan diri "tidak beragama".[9]
^Ivković, Sanja Kutnjak; Haberfeld, M.R. (10 June 2015). Measuring Police Integrity Across the World: Studies from Established Democracies and Countries in Transition (dalam bahasa English). Springer. hlm. 131. ISBN9781493922796. Estonia is considered Protestant when classified by its historically predominant major religion (Norris and Inglehart 2011) and thus some authors (e.g., Davie 2003) claim Estonia belongs to Western (Lutheran) Europe, while others (e.g., Norris and Inglehart 2011) see Estonia as a Protestant ex-Communist society.Pemeliharaan CS1: Bahasa yang tidak diketahui (link)
^ abTriin Edovald; Michelle Felton; John Haywood; Rimvydas Juskaitis; Michael Thomas Kerrigan; Simon Lund-Lack; Nicholas Middleton; Josef Miskovsky; Ihar Piatrowicz; Lisa Pickering; Dace Praulins; John Swift; Vytautas Uselis; Ilivi Zajedova (2010). World and Its Peoples: Estonia, Latvia, Lithuania, and Poland. Marshall Cavendish. hlm. 1066. ISBN9780761478966. It is usually said that Estonia is a Protestant country; however, the overwhelming majority of Estonians, some 72 percent, are nonreligious. Estonia is the European Union (EU) country with the greatest percentage of people with no religious belief. This is in part, the result of Soviet actions and repression of religion. When the Soviet Union annexed Estonia in 1940, church property was confiscated, many theologians were deported to Siberia, most of the leadership of Evangelical Lutheran Church went into exile, and religious instruction was banned. Many churches were destroyed in the German occupation of Estonia, from 1941 through 1944, and in World War II (1939-1945), and religion was actively persecuted in Estonia under Soviet rule 1944 until 1989, when some measure of tolerance was introduced.
^Rausing, Sigrid (2004). History, Memory, and Identity in Post-Soviet Estonia: The End of a Collective Farm (dalam bahasa English). Oxford University Press. hlm. 96. ISBN9780199263189. Protestantism has done much to inform the moral world view of the Estonians, particularly the process of distinguishing themselves from the Russians.Pemeliharaan CS1: Bahasa yang tidak diketahui (link)
^Ringvee, Ringo (16 September 2011). "Is Estonia really the least religious country in the world?". The Guardian. For this situation there are several reasons, starting from the distant past (the close connection of the churches with the Swedish or German ruling classes) up to the Soviet-period atheist policy when the chain of religious traditions was broken in most families. In Estonia, religion has never played an important role on the political or ideological battlefield. The institutional religious life was dominated by foreigners until the early 20th century. The tendencies that prevailed in the late 1930s for closer relations between the state and Lutheran church [...] ended with the Soviet occupation in 1940.Tidak memiliki atau membutuhkan |url= (bantuan); Parameter |access-date= membutuhkan |url= (bantuan)