Menahem was born in Asmara, Eritrea, in 1921 to Miriam and Amram Tze’iri. In the family, there were four brothers and two sisters. It was a traditional Yemenite family, which moved from Aden to Asmara. The father was a fabric merchant who travelled to the villages, while the mother was a seamstress.
When Menahem was born, his parents returned to Aden, sailing to Egypt, by way of the Suez Canal, to the Land of Israel, which they reached in 1930. They settled in Kerem HaTeimanim. Menahem studied in school in the neighborhood. The father took odd jobs as they were available.
In 1940, Menahem enlisted in the British Army, serving as a driver in Egypt, elsewhere in Africa, in Sudan and in Libya. He served until 1946, and he joined Lehi while in the British Army, using his travel between Egypt and the Land of Israel to bring posters and promotional materials to the Jewish youth clubs in Cairo. After demobilization, he joined the operations division. He took part in the bombing of the Intelligence building on Jaffa Road in Tel Aviv, together Blond Dov. He was also part of the group who blew up British Army vehicles. Menahem also surveilled and tracked individuals in preparation.
In 1948, at Sheikh Munis, he joined the IDF with other Lehi members. He fought in Battalion 89 of 8th Brigade, under Blond Dov. At the beginning of his service, at the Battle of Beit Naballah, he was injured and hospitalized for a while in the military hospital. Afterwards, he was discharged and found work as a driver, which he did for a number of years.
In 1954, he married his relative Miriam Tze’iri. He then began working in the marketing of citrus fruit, as an inspector and supervisor of a packing plant. Eventually, he was put in charge of the wholesale market in Tel Aviv. He worked in this field until his retirement.
Menahem and Miriam had four children.