In August 1520 Martin Luther published An den Christlichen Adel Deutscher Nation; von des Christlichen Standes Besserung (To the Christian Nobility of the German Nation). This and two other tracts he published in 1520—On the Babylonian Captivity of the Church, and On the Freedom of a Christian—became manifestos of the Reformation.
" 'To the Christian Nobility' was published in the middle of August 1520 and by the eighteenth of the month four thousand copies were sold; seventeen further editions were published in the sixteenth century. It was shortly followed by the two other revolutionary tracts: 'Concerning Christian Liberty' (on justification by faith alone) and 'On the Babylonian Captivity of the Church' (criticizing the sacramental system of the Church)" (Carter & Muir, Printing and the Mind of Man  no. 49).