He was born in 1873 in Ditkowice near Tarnopol (today’s Ternopil), to a well-known Jewish family. He fought in the First Brigade of the Polish Legions. Choosing field service at his own request, he began it as a regular private.

As a young man, he studied at secondary schools in Tarnopol and Kraków. In 1890 he was called up to the Austro-Hungarian army, and in 1892 was appointed lieutenant of infantry reserve. In 1896, he obtained a doctorate in law from the Jagiellonian University. In the same year, he was employed at the Treasury Procurator’s Office in Lwów (today’s Lviv), and then moved to Kraków. He systematically climbed the ranks of his career ladder. In 1909, he was promoted to financial counsellor of the Galician Treasury Procuratorate and moved again to Lwów.

Both in Krakow and in Lwów he was a well-known participant in cultural life, a member of many social and cultural organisations, and a collector of works of art. He collected paintings (by Aleksander Gierymski, Stanisław Wyspiański, Jacek Malczewski, Maurycy and Leopold Gottlieb), prints, sculptures, ex-librises, folk art objects, maps, manuscripts (by Juliusz Słowacki, among others), and Jewish artefacts. He published texts on historical topics.

In Lwów, he became involved with the Polish Gymnastic Society “Falcon” and attended an officer’s course of that organisation. He was in favour of cooperation with other Polish patriotic organisations and the militarisation of “Falcon” activities.

At the outbreak of the First World War, he was called up to the Austrian army in the rank of second lieutenant. In October 1914, he asked to be transferred to the First Brigade of the Polish Legions. He was assigned to the recruitment office of the Supreme National Committee, where he was one of Lt. Władysław Sikorski’s closest associates. From July 1915, he was in the field service, in the 3rd Company of the 3rd Battalion of the 1st Infantry Regiment of the Polish Legions. In the battle of Jastkow he was wounded. After returning to duty, he was promoted to corporal. He fought, among other battles, at Kostiuchnówka, Jablonka, Wólka Hałuzińska, Maniewicz and Haluz. On 25 October 1915, he was killed at Kukly. His death was reported in Galician newspapers such as the “Kurjer Lwowski” and “Nowości Ilustrowane”.

Sternschuss’s collection, in accordance with his will, was donated to the National Museum in Krakow, as well as to other museums. He was posthumously awarded the Silver Cross of the Order of Virtuti Militari and the Cross of Independence.