Born in Akmenė, Lithuania on 6 January 1894[1] and later educated in Moscow, Šimaitė became a librarian at Vilnius University in 1940.

She began entering the ghetto under the pretext of recovering library books from Jewish university students.

After the camp was liberated by the Allies, Šimaitė remained in France, working as a librarian, except for a period from 1953 to 1956 spent in Israel.

On 15 March 1966, the Israeli organisation Yad Vashem recognized Šimaitė as a Righteous Among the Nations, planting a tree in her honour.

[4] After the war, she moved to Paris and continued to work in a library while corresponding with friends, intellectuals, and public figures around the world.