Born and educated in Tel Aviv, Dinitz joined the pre-State Haganah forces and fought in Israel's War of Independence.
He held a B.Sc. from the School of Foreign Service, Georgetown University and anM.Sc. in International Law.

Dinitz's academic education in the United States (1951-1957) fitted him for a diplomatic career, especially in relation to the United States. He also held political and other public positions, as well as lecturing in the field of International Law. For over 35 years, he served terms of office in the most distinguished positions in the major arenas of Israel's international and national activity and held six honorary doctorates - including one from his alma mater and others from the four most prestigious Jewish universities in the USA.

His first position at the Israel Foreign Ministry (1958-1960) was in the Information Department; from 1960-1963 he headed the Director-General's office.

Dinitz served in his first political post under Prime Minister Golda Meir as Political Secretary (1963-1966), but this later became a diplomatic appointment, when he became a major figure in Israel's delegation to the UN, during the significant pre-1967 period.
His only European appointment was to the Israel Embassy in Rome in 1966 (-1968), which is always considered a significant international and diplomatic appointment, because the position covers representation to the Vatican, at the center of the Catholic world and the focal point of what were unresolved controversies over the Vatican's role in the Shoah.

In 1968, Simcha Dinitz was posted to the US, serving as Information Attache at the Israel Embassy, but returned in 1969 to serve in the Prime Minister's Office under Golda Meir, first as Political Advisor, then as Director-General, only returning to the Foreign Service in 1973. The aftermath of the Six Day War in the international setting placed heavy demands on the Office.

From 1973-1978, Dinitz served in the premier position of Israeli Ambassador to the US, a period coinciding with the Yom Kippur War, during which he convinced President Nixon (then intensely involved in the Vietnam conflict) to authorise a US armaments air-bridge to Israel. He was admired both by those in the echelons of political power in the US and the Jewish community. His term of service coincided with the most dramatic developments in the Middle East conflict, including participating in the delegation to the Egypt-Israel peace accords at Camp David, and it also covered a period of intense diplomatic activity about Israel at the UN, where Israel needed US support.

Dinitz returned to Israel during the period of the first Likud government under Prime Minister Menachem Begin, and this is the only time at which he held academic appointments, first as Vice-President of the Hebrew University of Jerusalem and later as Chairman of the University's Leonard Davis Institute for International Relations (1979-1984).

In 1984, Dinitz entered the 11th Knesset as a member of the Labor Alignment (Ma'arach) in the National Unity Government http://www.knesset.gov.il/history/eng/eng_hist11_s.htm , and served on the House Committee and the Foreign Affairs and Defense Committee http://www.knesset.gov.il/history/eng/eng_hist11.htm .

He did not complete the term, as he was elected Chairman of the Jewish Agency Executive in 1987 at the Thirty-First Zionist Congress, during a critical period in the Agency's restructuring process, which were overshadowed from 1990 onwards by the immense efforts required of the Agency and the State of Israel to absorb a massive wave of Aliyah from the USSR during its period of disintegration, as well as from Ethiopia http://www.jafi.org.il/education/100/concepts/cong31.html.
He was later re-elected at the World Zionist Congress of 1992 http://www.jafi.org.il/education/100/concepts/cong32.html , but he stepped down in 1994.

From 1994 onwards, Simcha Dinitz published many articles and was much in demand as an academic lecturer in the field of Israel's Foreign Relations and Defense, and with particular reference to issues of International Law.

He died in Israel, of a heart attack, in September 2003, aged 74. He is survived by his wife, Vivian, his children, Michael, Dorit and Tamar and eight grandchildren.

Jewish Agency for Israel http://www.jafi.org.il/dinitz.htm

Israel Ministry of Foreign Affairs http://www.mfa.gov.il/mfa/go.asp?MFAH0ntc0