The 19th century marked a new approach in terms of content within the Reformed church family. In the 17th century, the formation of confessions with their doctrinal consolidation within the framework of the Reformed Orthodoxy came to a temporary standstill, but this flourished again at the beginning of the 19th century under changed theological and church-political signs. In addition to established Reformed territorial churches, independent Reformed churches also endeavored to testify to their faith anew in their own individual circumstances. Volume 4/1 documents this reformed creed of the 19th century; During these decades, the geographical scope expanded beyond Europe to Asia and North America. The individual confessional texts were introduced and edited by William Black, Eberhard Busch, Emidio Campi, Rieke Eulenstein, Philip H. Eveson, Matthias Freudenberg, Pierre-Yves Kirschleger, David Komline, Andreas Mühling, Peter Opitz, Georg Plasger and Yoshiki Terazono.