Education
Ivinskis studied at Telšiai and Plungė gymnasiums. In 1925 he entered the University of Lithuania to study philosophy, but later changed the subject to history. In 1929, Ivinskis received a grant to continue his studies in Germany.
There, under the direction of Professor.
Albert Brackmann, he received a Doctor of Philosophy for his thesis Geschichte des Bauerstandes in Litauen (English: History of the Conditions of Lithuanian Farmers) in 1932. In 1933 in Gdańsk he was habilitated for his work Lietuvių ir prūsų prekybiniai santykiai pirmojoje XVI a. pusėje (English: Lithuanian and Prussian trade in the first half of the 16th century).
After returning to Lithuania he was drafted into the army.
During his free time, he gave lectures at the and in 1940 became an extraordinary professor In that year he was invited to work at the Vilnius University.
He served as the dean of Faculty of Theology–Philosophy at the Vytautas Magnus University from 1941 to 1942.
Foreign his active public defense of university autonomy, the Nazis listed him among other prominent public figures to be transferred to Stutthof concentration camp. Ivinskis was saved from death because he was ill, and was hospitalized for half a year.