John Knox (c. 1510 – 24 November 1572) is a Scottish clergyman and leader of the Protestant Reformation who is considered the founder of the Presbyterian denomination.

He is believed to have been educated at the University of St. Andrews and worked as a notary-priest.

Influenced by early church reformers such as George Wishart, he joins the movement to reform the Scottish church.

He is caught up in the ecclesiastical and political events that involve the murder of Cardinal Beaton in 1546 and the intervention of the regent of Scotland, Mary of Guise.

He is taken prisoner by French forces the following year and exiled to England on his release in 1549.

While in exile, Knox is licensed to work in the Church of England, where he quickly rises in the ranks to serve King Edward VI of England as a royal chaplain.

In this position, he exerts a reforming influence on the text of the Book of Common Prayer.

In England he meets and marries his first wife, Marjorie.

When Mary Tudor ascends the throne and reestablishes Roman Catholicism, Knox is forced to resign his position and leave the country.

Knox first moves to Geneva and then to Frankfurt.

In Geneva, he meets John Calvin, from whom he gains experience and knowledge of Reformed theology and Presbyterian polity.

He creates a new order of service, which is eventually adopted by the reformed church in Scotland.

He leaves Geneva to head the English refugee church in Frankfurt but he is forced to leave over differences concerning the liturgy, thus ending his association with the Church of England.

On his return to Scotland, he leads the Protestant Reformation in Scotland, in partnership with the Scottish Protestant nobility.

The movement may be seen as a revolution, since it leads to the ousting of Mary of Guise, who governs the country in the name of her young daughter, Mary, Queen of Scots.

Knox helps write the new confession of faith and the ecclesiastical order for the newly created reformed church, the Kirk.

He continues to serve as the religious leader of the Protestants throughout Mary's reign.

In several interviews with the queen, Knox admonishes her for supporting Catholic practices.

Eventually, when she is imprisoned for her alleged role in the murder of her husband, Lord Darnley, and James VI enthroned in her stead, he openly calls for her execution.

He continues to preach until his final days.