The Brownists were a Christian group in 16th-century England. They were a group of English Dissenters or early Separatists from the Church of England. They were named after Robert Browne, who was born at Tolethorpe Hall in Rutland, England, in the 1550s. The terms Brownists or Separatists were used to describe them by outsiders; they were known as Saints among themselves.

A majority of the Separatists aboard the Mayflower in 1620 were Brownists, and the Pilgrims were known into the 20th century as the Brownist Emigration.

The Brownists were eventually absorbed into the Mennonite Church, while others joined the Baptist Church.

There had been early advocates of a congregational form of organisation for the Church of England in the time of Henry VIII. It became clear that the English government had other plans on the re-establishment of the Anglican Church, after the Catholic Mary's reign, and these dissenters looked towards setting up a separate church.

The first wave of separatism from the Elizabethan Church of England came in London after March 1566, when Archbishop Parker enforced strict adherence to the Prayer Book and 14 ministers were deposed from office. Some of the most radical led their followers in forming the London Underground Church, meeting in secret locations. From possibly a thousand members at its height, this movement shrank, through imprisonment and deaths, to a small group of members in Browne's days. He and Robert Harrison knew of the London church, but seem to have believed it had died.

Robert Browne (d. 1633) was a student who became an Anglican priest late in life. At Cambridge University, he was influenced by Puritan theologians, including Thomas Cartwright (1535–1603).

Browne became a Lecturer at St Mary's Church, Islington where his dissident preaching against the doctrines and disciplines of the Church of England began to attract attention. During 1578, Browne returned to Cambridge University and came under the influence of Richard Greenham, puritan rector of Dry Drayton. He encouraged Browne to complete his ordination and serve at a Church of England parish church. Browne was offered a lecturer position at St Bene't's Church in Cambridge, possibly through Greenham, but his tenure there was short. Browne came to reject the puritan view of reform from within the Church, and started to look outside the established Church.

In 1581, Browne had become the leader of this movement and, in Norwich, attempted to set up a separate Congregational church outside the Church of England. He was arrested but released on the advice of William Cecil, his kinsman. Browne and his companions left England and moved to Middelburg in the Netherlands later in 1581. There they organised a church on what they conceived to be the New Testament model, but the community broke up within two years owing to internal dissensions.