[1] On 4 November 1918, one week before the Armistice of Villa Giusti, he became an Italian prisoner of war.

[1] After returning to Austria, he attended the University of Vienna, where he earned his PhD in 1920, with a thesis written under the supervision of Gustav von Escherich and Wilhelm Wirtinger.

[1][2] In autumn 1928 he married his first wife Klara Riccabona, who later died while giving birth to their sixth daughter.

[3] He lends his name to a few mathematical concepts: Vietoris remained scientifically active in his later years, even writing one paper on trigonometric sums at the age of 103.

[4] Vietoris lived to be 110 years and 309 days old, and became the oldest verified Austrian man ever.