England has been a Christian country since it was annexed by the Roman Empire in 44 AD. The Church of England (Anglican Church) was founded by King Henry VIII who left the Roman Catholic Church when it refused to grant his request for a divorce. The Queen is the head of the Church of England (called the "Defender of the Faith"). The Prime Minister provides the head of state with nominations for bishops, which the head of state then appoints. Despite the UK’s apparent link with Christianity, churches do not receive direct funding from the government.

Scotland’s introduction to Christianity came via the monastic centre at Whithorn in the 4th century and through Colmcille, who established a place of learning on the island of Iona in the 6th century. These two events started the "Celtic" Church, which has left its mark on Scottish spirituality. The Church of Scotland is the national church. It differs from the Church of England in that it has a Presbyterian form of governance.

Religion in the UK, for the most part, has little impact on everyday life. Since 1980, there has been a significant decrease in church membership among the Christian population. Although church attendance and organized religion are on a decline, the British retain a strong cultural attachment to Christianity.

Many Britons visit churches and admire them for their architectural and historical contribution to British life. However, the vast majority of the population only attends church services at Christmas or Easter or to participate in the rituals of christenings, weddings, and funerals. In many ways, this is much like the British themselves—pragmatic and unobtrusive.

This is an increasingly ethnically diverse and multicultural society. While the observance of Christianity may be on the wane, other religions, such as Islam and Hinduism, are rising rapidly, particularly in London, the Midlands and northern cities that are home to large immigrant communities.