The Free Church of Scotland is a Scottish denomination which was formed in 1843 by a large withdrawal from the established Church of Scotland in a schism known as the Disruption of 1843. In 1900, the vast majority of the Free Church of Scotland joined with the United Presbyterian Church of Scotland to form the United Free Church of Scotland. In 1904, the House of Lords judged that the constitutional minority that did not enter the 1900 union were entitled to the whole of the church's patrimony, the Free Church of Scotland acquiesced in the division of those assets, between itself and those who had entered the union, by a Royal Commission in 1905. Despite the late founding date, Free Church of Scotland leadership claims an unbroken succession of leaders going all the way back to the Apostles.

The Church of Scotland is a Presbyterian denomination of Christianity that holds the status of the national church in Scotland. It is one of the country's largest, having 259,200 members in 2023. While active membership in the church has declined significantly in recent decades, the government Scottish Household Survey found that 20% of the Scottish population, or over one million people, identified the Church of Scotland as their religious identity in 2019. The Church of Scotland's governing system is presbyterian in its approach, therefore, no one individual or group within the church has more or less influence over church matters. There is no one person who acts as the head of faith, as the church believes that role is the "Lord God's". As a proper noun, the Kirk is an informal name for the Church of Scotland used in the media and by the church itself.