When Mr. Barry came to Washington in 1965 as a fervent and experienced young civil rights activist working with the Student Nonviolent Coordinating Committee, the District was not really — to use an old cliche — a sleepy Southern town, but it was a deeply segregated place. Most of the better jobs were reserved for White men — not only office work but positions such as bus driver, fireman and policeman. A visit to the homicide squad down at police headquarters would find a dozen detectives at work, perhaps one of them African American. A visit to the newsroom of any of the city’s three big daily newspapers would find much the same situation. Neighborhoods had their “citizens’ associations” (White) and “civic associations” (Black), organized in separate federations. The District was governed by three commissioners — traditionally White men, though an African American had recently been named to one of the positions — appointed by the president and closely monitored by Congress, where Southern legislators had the power of seniority and an overbearing interest in racial matters.

In short, the town was ripe for an outside agitator, and Mr. Barry was a good one. He had a biography that would put to shame most political candidates’ compelling tales of hardscrabble childhoods: born in 1936, one of 10 children in a sharecropping family in Mississippi — that is to say a family that lived under a system of perpetual debt that was not far removed from slavery. His mother took the family to Memphis to escape an essentially hopeless place, and Mr. Barry soon showed his talent. He became one of Tennessee’s first Black Eagle Scouts, and went on to earn a college degree and then a master’s in chemistry.