Shlomo Weinstein (later Gazit) was born in Istanbul, Turkey, to a Ukrainian Jewish family which later moved to Palestine.

During the 1948 Arab-Israeli War, Gazit served in the Harel Brigade, and initially took part in fighting the Arab Legion, participating in the Battles of Latrun.

He served as the head of the assessment department in IDF intelligence before the Six-Day War, but then took leave to study for a master's degree in history.

Gazit's studies were interrupted in the summer of 1967, when he was appointed by Defense Minister Moshe Dayan to be in charge of a committee tasked with running the political, security, and later economic affairs in the newly captured territories.

Upon his retirement from the IDF, he served as president of the Ben Gurion University in Beersheba for two four-year terms, following Yosef Tekoah.