(Schornreute near Ravensburg 1868 – 1933 St. Vincenz Rottenmünster private asylum near Rottweil).

After his father's death in 1871, Natterer grew up in Stuttgart, where he did an apprenticeship as an electrician before joining the Stuttgart Grenadier Regiment in 1888 as a "one-year volunteer". He was unable to study for financial reasons. So he worked in various companies, in Germany, Switzerland, France and the USA, married in 1896, founded his own business in Würzburg in 1897, and then trained apprentices himself. Building equipment for the university, including for Wilhelm Röntgen, was prestigious and lucrative. When they hired their own locksmith there in 1902, this business relationship was broken off. Natterer got into financial difficulties, became withdrawn, and devoted himself to his inventions. On 1 April 1907, at 12 noon, he saw fantastic images above the Rothebühl barracks in Stuttgart in rapid succession within half an hour, and was convinced that they were "revealed to him by God for the completion of salvation". With agonising bodily sensations (a broom sweeping in his chest, animals coming out of his nose, etc.), which urged him to commit suicide, he was sent to the Rottenmünster asylum near Rottweil in October. In 1909, he was transferred to the Weissenau sanatorium, where he began to draw in 1911, especially after having experienced his vision. From 1912 onwards, he was convinced that he was a descendant of Napoleon I and was, as August I, IV Napoleon, the French emperor. He believed the war had begun for his liberation. When the institution became a military hospital, Natterer was transferred back to Rottenmünster in 1917. Here, in addition to his "imperial office", he was busy working in the locksmith's shop, especially repairing clocks. It was only shortly before his death, after four years of renewed agonising body sensations, did Natterer begin to draw again.