While Mr. Wolff was in Spain, he became a friend of Ernest Hemingway, who served him his first glass of Scotch; Hemingway was in Spain as a reporter and wrote fiction about the conflict as well. Later, in a pamphlet issued when sculptures of the fighters were unveiled, he called Mr. Wolff “as brave and as good a soldier as any that commanded battalions at Gettysburg.”

After the exhausted volunteers arrived in New York aboard the ocean liner Paris on Dec. 15, 1938, it was Mr. Wolff who laid a wreath outside the railing of Madison Square Park, kept out of the park for want of a permit.

Mr. Wolff never stopped defying authority. He helped lead the fight against United States support of Franco’s government and battled fiercely for civil rights and against the Vietnam War. He even offered the services of the aging veterans of the Lincoln Brigade to the North Vietnamese leader, Ho Chi Minh, who declined them.

Mr. Wolff was born in the Bensonhurst section of Brooklyn on Oct. 7, 1915. He dropped out of high school and joined the Civilian Conservation Corps, a New Deal program for unemployed youths. He was dropped when he protested what he considered the poor treatment of an injured friend, Mr. Carroll said.

He found a job in the garment district and joined the Young Communist League. When a leader called for volunteers to go to Spain, Mr. Wolff raised his hand. He considered himself a pacifist and planned to serve as a medic, but switched to a machine-gun company when his Washington battalion went into action at Brunete in July 1937.

The American volunteers were not actually members of a Lincoln Brigade, though that famous term was commonly used, even among veterans. Some, like Mr. Wolff, joined the Washington Battalion, others, the Lincoln Battalion. These battalions, and two others from other countries, made up the 15th International Brigade.

After the Washington Battalion suffered crushing casualties, it was merged into the Lincoln Battalion. More than 900 of the 3,000 American volunteers in these battalions were killed. It is believed that fewer than 40 are still living.

Mr. Wolff was fighting on the Aragon front in March 1938 and became commander when an artillery hit destroyed the battalion headquarters and killed several ranking officers. Then a captain, he led soldiers through perilous retreats and wandered behind enemy lines until they managed to swim across the Ebro.

One day, Robert Capa, the legendary photographer, snapped Mr. Wolff standing next to Hemingway. The photo appeared on the cover of The Forward, and for the first time his mother knew her son was in combat. He had told her he was working in a factory to free a Spanish loyalist for hazardous duty.

Mr. Wolff always said he first met Hemingway after stealing his mistress, something he told Salon in 1999 that Hemingway did not mind. Hemingway minded more when he found out that Mr. Wolff had no idea who he was. For his part, Mr. Wolff resented Hemingway’s description of villagers loyal to the Republic as having murdered fascists in “For Whom the Bell Tolls.”

Mr. Wolff is survived by his daughter, Susan Wallis of Vermont; his son, Peter, of Connecticut; four grandchildren; and nine great-grandchildren.

Mr. Wolff said he was turned down for combat duty in World War II because of concerns about his leftist politics. He later fought successfully against the “subversive” label pinned on the Lincoln veterans for decades. He personally delivered 20 ambulances to the Nicaraguan government when the Reagan administration was supporting rebels against it.

One of his battles after the civil war was leading his veterans to urge the Brooklyn Dodgers to integrate. “The guys were all Dodgers fans,” he said. “It was a way to carry on the struggle.”

By DOUGLAS MARTIN. Published January 17, 2008

From The New York Times. Obituaries