Background
Wiesemann was born in Herford, North Rhine-Westphalia in the archdiocese of Paderborn.
Wiesemann was born in Herford, North Rhine-Westphalia in the archdiocese of Paderborn.
He became a chaplain on 10 October 1985 in Rome. He later served as a priest in Bösperde, a suburb of Menden and provost of Saint Petrus and Andreas in Brilon. In 2002 Pope Pope John Paul II named him Auxiliary bishop, which he was ordained on 8 September 2002 in Paderborn cathedral.
On 19 December 2007 Pope Benedict XVI named him the successor to bishop Anton Schlembach.
He ascended to the office on 2 March 2008 in the Speyer cathedral.