Werner Michael Blumenthal (born January 3, 1926) is a German-American business leader, economist and political adviser who served as United States Secretary of the Treasury under President Jimmy Carter from 1977 to 1979.

At age thirteen, Blumenthal barely escaped Nazi Germany with his Jewish family in 1939. He was forced to spend World War II living in the ghetto of Japanese-occupied Shanghai, China, until 1947. He then made his way to San Francisco and began doing odd jobs to work his way through school. He enrolled in college, eventually graduating from University of California, Berkeley and Princeton University with degrees in international economics. During his career, he became active in both business and public service.

Before being appointed to a cabinet position with newly elected President Jimmy Carter, Blumenthal had become a successful business leader and had already held administrative positions under Presidents John F. Kennedy and Lyndon B. Johnson. As a member of the Carter administration, he helped guide economic policy and took part in re-establishing ties with China. After he resigned, he became chairman and CEO of Burroughs Corporation and Unisys, followed by seventeen years as director of the restored Jewish Museum in Berlin. He is the author of The Invisible Wall (1998, Counterpoint Press) and From Exile to Washington: A Memoir of Leadership in the Twentieth Century (2013, The Overlook Press). Blumenthal is the oldest living former U.S. Cabinet member.

Blumenthal was born in Oranienburg, Weimar Republic (present-day Germany), the son of Rose Valerie (née Markt) and Ewald Blumenthal. His family was of modest means as owners of a dress shop. His forebears had lived in Oranienburg since the 16th century. As a result of the Nazi party's Nuremberg Laws, which took effect in 1935, his family began to fear for their lives and realized they had to escape from Germany. Blumenthal recalled Kristallnacht, a series of coordinated attacks against Jews and their property which began throughout Germany on November 9, 1938, when he was 12 years old:

I clearly remember ... when they came and smashed all the Jewish stores. I remember seeing the largest synagogue in Berlin burn, and I remember being beaten up by kids in uniform.

Nazi Gestapo men forced their way into his home early one morning in 1938 and arrested his father for no stated reason. His father was taken to Buchenwald concentration camp, one of the largest forced labor camps in Germany, where an estimated 56,000 people, mostly Jews, were eventually killed. His mother hastily sold all their household possessions and managed to win her husband's release. They had no choice but to sell their long-established dress store to their managing saleswoman for "practically nothing," says his older sister Stefanie. She recalls, "My mother wept—not so much out of the loss, but out of a sense of the unfairness of it, that someone we'd trained could turn on us, could get something we had worked so hard for, for nothing."

With their little remaining money, his mother bought tickets for them to go to Shanghai, China, an open port city which didn't require a visa. They fled Germany on a passenger-carrying freighter shortly before war broke out in 1939. They took only minimal possessions; they were not allowed to take any money. He remembers the voyage: "From Naples via Port Said, Suez, Aden, Bombay, Colombo, Singapore, and Hong Kong; each one of those ports of call was part of the British Empire, and none would admit Jewish refugees."

Upon arriving, they expected to remain only briefly, assuming they could then travel on to a safer country. However, with the outbreak of World War II, Japan had occupied Shanghai, and the Blumenthals were confined to the Shanghai Ghetto along with 20,000 other Jewish refugees for the next eight years.