The Marprelate Tracts were a series of seven printed pamphlets appearing in late 1588. The tracts, whose authorship was a well-guarded secret, lampooned individual bishops in the Anglican church, and viciously attacked the church in general. They were signed 'Martin Mar-Prelate', and thus became known as the Marprelate Tracts.
The government of Elizabeth I went to great lengths to track down those responsible for the publication of the tracts, and eventually executed one man, John Penry. The author of the Marprelate Tracts was never uncovered, but the finger of suspicion points at a man named Job Throckmorton.
Though not of any great importance themselves, the Marprelate Tracts were part of a larger movement of presbyterian radical reform of the established church.
The late Elizabethan church was in great flux, with more or less incompatible sects struggling to gain the upper hand. A severe Court of High Commission was set up to deal with ecclesiastical matters, and the Court gained a reputation for severity and high-handed action. The more severely the Court of High Commission acted, and the more it tried to enforce rigid uniformity in religious matters, the louder bayed the voices of its opponents.
The established Church responded to the tracts and other similar voices for reform with an increasingly severe crackdown on Catholicism and all other forms of non-conformist theology. In a sense, the Church leadership turned its energy in two directions at once; against the Catholics at one extreme, and more radical religious reformers at the other extreme.
A few of the non-conformists left the country, but most stayed, not just within England, but within the Church as well; choosing to continue their clamour for reform from within the church rather than without it. Eventually, the established church metamorphosed into the so-called 'High Church', while the reformers became what we now know as the Puritans.