Arnim was born in the Prussian capital Berlin, the son of envoy Friedrich Abraham Wilhelm von Arnim and his wife Georgine von Wallmoden-Grimborn, a daughter of the Hanoverian field marshal and art collectorJohann Ludwig von Wallmoden-Gimborn and thereby presumably a granddaughter of King George II of Great Britain. His parents divorced, when he was three years old. Having finished his studies in Berlin and Göttingen in 1825, he joined the Prussian Guards Uhlans regiment as One-year volunteer and afterwards entered civil service at the Kammergericht. In 1830 he was appointed Landrat official in the Uckermark district and in 1833 he became Vice-president of the Pomeranian Stralsund government region. One year later he later assumed the position of President in the Aix-la-Chapelle region, from 1838 in Merseburg, Saxony. In 1840 he became governor of the Grand Duchy of Posen. In 1842 Arnim was called back to Berlin, to be appointed Prussian State Minister of the Interior. Nevertheless, he resigned in 1845, after his plans to draft a Prussian Constitution were aborted by King Frederick William IV. When the March Revolution broke out in 1848, his services were again in demand. From 19 March 1848 he acted as the first Prussian Minister President and Foreign Minister, however, he again resigned within a few days, after the king chose to place himself at the head of the revolutionary movement. A member of the Provincial Brandenburg Landtag assembly since 1839, Arnim from 18 May to 10 June 1848 was a representative for Prenzlau in the Frankfurt Parliament and also was a member of the short-lived Erfurt Union Parliament in 1850. He belonged to the newly established Prussian House of Representatives from 1849 and later joined the House of Lords chamber of the Prussian Prliament. 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. The verses were published in the Vorwärts!weekly newspaper after an 1844 riot in the Province of Silesia, which later also inspired the drama The Weavers by Gerhart Hauptmann. 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". 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. Arnim died on 8 January 1868 at his Boitzenburg estate.
