As I have indicated, however, there were those who refused to submit to the ideology and policies of the German Christian movement. Indeed, they opposed them, sometimes actively and sometimes passively, through their participation in the Kirchenkampf and the Confessing Church. The official beginning of the Confessing Church is usually identified with the meeting of the Confessing Synod of German Evangelical Churches in Barmen from May 29-31, 1934. It was, of course, at Barmen that the Confessing Church adopted the Barmen Declaration. The document itself was produced by Hans Asmussen, a Lutheran, and by Karl Barth, a Swiss Reformed theologian teaching in Germany at the time. Barth was, of course, the leading spirit behind the Barmen Declaration.
~Kurt Hendel, “The Historical Context of the Barmen Declaration” in Currents in Theology and Mission, vol. 36, no. 2, 134.