Julius Rupp (1809-1884) was a vocal and free-thinking Protestant preacher/minister who lived and worked in Königsberg for his entire life, fighting vehemently against state interference in religion. Despite being viewed as a dangerous radical by the Prussian government, he had no shortage of support in his home town and held a number of high-profile positions including Chaplain of the Königsberg garrison, Member of the Prussian Chamber (a political post to which he was twice elected by the citizens of Königsberg) and Chief Editor of the Königsberg Sonntags Post newspaper.

The current memorial is a reproduction of an earlier one which had been erected outside his former house in 1909 by the Free Evangelical Community but was sadly destroyed during WW2. The epithet is a Rupp quote, written in German, and reads: ‘He who fails to live by the truth he believes, is the most dangerous enemy of truth itself.’