Islamdominates Kuwaiti identity, and the constitution states that "the religion of the state is Islam and the Sharia shall be a main source of legislation", but it also secures religious freedom for all faiths.
Immigrant workers have contributed with a substantial presence of Christianity, while Hinduism only has a few adherents.
Islam in Kuwait is dominated by Sunni, but with a substantial Shi'i minority. Relations between the two groups have grown increasingly tensed since the 1980's, much motivated by the Iranian revolution of 1979, which made Shi'i the state religion of Iran.
Sunnis of Kuwait belong to the Maliki branch (madhhab) of law and theology (Sharia), setting them apart from neighbouring Saudi Arabia, where Hanbali dominates.
The elite of the society, including the royal family, are Sunnis. To some extent, Sunnis have political and economic benefits compared to Shi'is, but there is far less discrimination than in neighbouring Arab countries.
The size of the Shi'i community is not clear, estimates vary a lot, from about 13% to 25% of the population as a whole. Shi'is are mainly Arabs, but there is a substantial community of Iranian origin.
Estimates of the Christian population can be as high as 12% of the population.
By far the largest Christian group is the Roman Catholic Church, which has a cathedral as their main point of gathering. Adherents to this church are largely from Asia, countries like Philippines and Sri Lanka. Maronite Christians from Lebanon also attend the Roman Catholic churches.
The second largest church is the Coptic, with adherents among the Egyptian community of foreign workers.
Information about Christian Kuwaiti citizens is conflicting, as some sources indicate that citizenship is only for Muslims (law of 1981, but apparently repealed). The number of Christian citizens is set to about 200, people with backgrounds from Turkey, Iraq, Lebanon, Syria and Palestine.