Nachman was born on 24.4.1919 in the German Colony, Tarutyne, in southern Bessarabia, to Eliyahu and Rivka née Glazer. The family was well-off, traditional and Zionist. On his father’s side, he was descended from Rabbi Levi Yitzhak of Berdychiv. The parents were general Zionists and active in the community.

Nachman finished nine years in elementary school and in the Hebrew Gymnasium, and he excelled in his studies, though he did not invest much time in them. He was simply born with exceptional talents. He could speak seven languages fluently (Yiddish, Hebrew, German, Russian, Romanian, French and English). He could sing and play piano, and he was also skilled in painting and drafting.

In 1933, Nachman helped organize the first Beitar cell in Tarutyne. After a year, its commander, Tzvi Vinsman, made aliyah, so fifteen-year-old Nachman took over the cell. This was during the time of Arlozorov’s murder, and Nachman’s parents initially were sharply opposed to his Beitar activity, but they were soon persuaded that this was mere political provocation, and they joined Jabotinsky’s movement as well.

In 1938, Nachman completed his studied and graduated with honors from the public gymnasium in Kishinev. His father presented him with three options: studying engineering in France, working as a secretary in the family business of marketing agricultural and industrial equipment, or making aliyah with a certificate in order to study at Hebrew University in Jerusalem. Nachman chose the fourth option, making aliyah illegally with the Af al Pi program, on the Astir. He explained that as long as the British were in control, there was no time to study, and he did not need their approval to emigrate to the homeland.

He joined the IZL, then followed Yair to Lehi. After the 8 Yael Street operation, an explosion in which three police officers were killed, Nachman was a wanted man, with his picture publicized and put in all the newspapers, with a price on his head of two hundred pounds. He was in fact arrested in early 1942 in Haifa. He was sent to Latrun and Mizra, then exiled with the group of 251 first deported to Africa. He returned only on 12 July 1948, with the last group.

He then enlisted in the IDF, serving until 1950, when he started working for the Tahal Group. He also began studying at Hebrew University in 1951, earning a PhD in geology. From 1973 to 1989, he was a senior lecturer, until he retired at age seventy.

He married Aviva Zack in December 1956.