[1] Having finished his studies in Berlin and Göttingen in 1825, he joined the Prussian Guards Uhlans regiment as a One-year volunteer and afterwards entered civil service at the Kammergericht.

Nevertheless, he resigned in 1845 because his plans for a constitution for Prussia were at odds with King Frederick William IV's romantic ideals.

Arnim is known to this day for his remarks as Prussian Interior Minister during the Vormärz era concerning Heinrich Heine's poem The Silesian Weavers.

In a report to King Frederick William IV he described Heine's poetry as "an address to the poor amongst the populace, held in an inflammatory tone and filled with criminal utterances" ("eine in aufrührerischem Ton gehaltene und mit verbrecherischen Äußerungen angefüllte Ansprache an die Armen im Volke").

Subsequently, the Royal Prussian Kammergericht banned the poem, which in 1846 led to a prison sentence for a person who had dared to publicly recite it.