WASHINGTON - At the height of Libya's civil war, J. Christopher Stevens dashed off to the rebel stronghold of Benghazi by cargo boat to help shape an assortment of Libyan politicians and militias into the cohesive unit that would defeat Moammar Gadhafi. A year-and-a-half later, the 52-year-old ambassador died as Islamists attacked a U.S. consulate in the same city.

Stevens' death deprives the United States of someone widely regarded as one of the most effective American envoys to the Arab world. In his unfailingly polite and friendly manner, Stevens brokered tribal disputes and conducted U.S. outreach efforts in Jerusalem, Cairo, Damascus and Riyadh. As a rising star in U.S. foreign policy, he cheerily retuned to Libya four months ago, determined to see a democracy rise where Gadhafi's dictatorship for four decades flourished.

"It's especially tragic that Chris Stevens died in Benghazi because it is a city that he helped to save," President Obama said Wednesday. "With characteristic skill, courage and resolve he built partnerships with Libyan revolutionaries and helped them as they planned to build a new Libya."

A native of Northern California, he was dispatched to Benghazi in the midst of heavy fighting in April 2011, ferrying to the city on a Greek cargo ship to set up America's central office for coordinating military strategy, financial assistance and political work with the Libyan opposition.

"He was loved by everybody," said Ahmed al-Abbar, a Libyan opposition leader during the revolution.

As Libya's postwar challenges persisted, Stevens jumped at the opportunity earlier this year when Obama asked him to be the next U.S. ambassador in the Libyan capital.

"He risked his life to stop a tyrant then gave his life trying to help build a better Libya," Secretary of State Hillary Rodham Clinton said at the State Department. "The world needs more Chris Stevenses."

Stevens came from a family of doctors and lawyers, but showed an early interest in foreign policy. At Piedmont High School near Oakland, Calif., he served as editor of the school newspaper and was active in the Model U.N. club.

"What a bore it is, waking up in the morning always the same person," said his quote in the 1978 high school yearbook. "I wish I were unflinching and emphatic and had big eyebrows and a Message for the Age."

Following his father, Jan Stevens, he graduated from the University of California, Berkeley in 1982. He then volunteered for the Peace Corps as an English teacher for two years in a remote village in Morocco's High Atlas Mountains - "and quickly fell in love with this part of the world." Still, his next step was a law degree from the University of California's Hastings College of Law in 1989 and employment as a trade attorney in Washington.

One day, said a former colleague recounting Stevens' retelling of the story, the young lawyer put his head down at his desk and said to himself, "I can't do this anymore." He decided then to apply for the Foreign Service, joining in 1991.

In a YouTube video just before leaving for Libya to take up his latest post of ambassador, Stevens said he was "thrilled to watch the Libyan people stand up and demand their rights" during the revolution.