Michael Sattler was one of the leaders of the Swiss Anabaptists. He initiated a meeting in 1527 in Schleitheim (near Schaffhausen), in which many representatives of the various Anabaptist movements took part. The "Schleitheim Confession" adopted there presented the first systematic statement of Anabaptist beliefs. The text on the title cover reads:
Brüderlich vereinigung etlicher Kinder Gottes / sieben artikel betreffend.
Item, ein Sendbrieff Michael Sattlers / an ein gemein Gottes / sampt kurzem / doch wahrhafftigem anzeig / wie er seine leer zu Rottenburg am Necker / mit seinem blut bezeuget hat.
Brotherly Union of A Number of Children of God / concerning Seven Articles.
Item, a Letter from Michael Sattler / to a godly parish / together with a short / but true Account / of how he Bore Witness to his Teachings with his Blood / in Rottenburg am Necker.
Cover of the Schleitheim Confession of 1527, printed 1560; source: with kind permission of the Schleitheim Museum, http://www.museum-schleitheim.ch.