In addition to his journalistic work, he wrote novels, short stories, biographies, poems and radio plays, and edited Westphalia and Low German writers.
During World War I, Castelle was head of the press and news department of the Deputy Generalkommando [de] of the VII Armeekorps.
From 1930, he was appointed as editor of the magazine Der Türmer, Monatsschrift für Gemüt und Geist the journalistic guideline of the paper, the successor of Die Bergstadt.
"[2] After the Machtergreifung by the Nazis and its allies, Castelle, who had joined the NSDAP in 1933, held key positions in the cultural bureaucracy of the new regime.
After Castelle had already been chairman of the NS cultural community for the Steinfurt district, he was appointed member of the advisory board of the Gaus Westfalen-Nord and leading employee of the Reichsschrifttumskammer [de].
He saw the "extermination" of "sub-humanity, which has its most dangerous emanations in communism and Bolshevism" as a prerequisite for this,[4] but he also used Der Türmer for anti-Semitic propaganda.
[7] After the end of the period of National Socialism, Castelle was arrested by the British military government and interned due to his Nazi exposure.
In the following phases of denazification, the assessments improved: "Activity as a poet and free artist is not only unhesitating but urgently desired" (1947).
[8] Under these conditions, he succeeded in working for broadcasting again, now mainly as the author of Münsterländer Platt [de] plattdeutsche radio plays.
In 2010 at the latest, a public discussion about "Castelleweg" began in Münster, focusing on the National Socialist burden on the eponym.
[12] In 2010, the discovery of the buried knowledge of Castelle's Nazi activities was followed in Steinfurt by a council discussion on the renaming of the "Castelleweg", which was recommended by the cultural committee.
The CDU parliamentary group had submitted the - rejected - proposal to keep the name, but to attach an additional sign with a QR code.