From 2001 to 2004, Feldenkirchen worked as a lobby correspondent for
Der Tagesspiegel newspaper in
Berlin. In 2004, he transferred to the head office of the German
Der Spiegel (magazine), where he first worked as an editor. He advanced to senior political reporter in 2006 and was subsequently appointed deputy editor in 2007. Since the summer of 2010, Feldenkirchen has held the position of columnist in the head office of
Der Spiegel. In 2014, he finished a one-year stint as foreign correspondent in Washington, US. Feldenkirchen produced his first 45-minute documentary on the life and career of
Wolfgang Schäuble. The film,
It is how it is, was premiered on German television in September 2012. Feldenkirchen joined
Martin Schulz to report on the five final months of the electoral campaign for the
Bundestag (German Federal Parliament) in 2017. He attended fifty events, ranging from strategy meetings to social gatherings, including Currywurst Dinners (a social occasion in the evening, where bratwurst sausage is served).
Der Spiegel published an exclusive about Schulz after the election results came in, as agreed with the politician beforehand. The portrayal of
Barack Obama in
The New Yorker served as a model for the feature story written by Feldenkirchen in November 2016. == Novels ==