Richard Hatcher, who became one of the first African American mayors of a large U.S. city when he was elected mayor of Gary, Ind., in 1967, died Dec. 13 at a Chicago hospital. He was 86.

His death was announced by his daughter, state Rep. Ragen Hatcher, a Gary Democrat. The cause was not immediately known.

Mr. Hatcher had to overcome opposition from the local Democratic machine to become mayor of what was then Indiana’s second-largest city in a surprise victory in 1967. He went on to serve five terms.

He became the political face of Gary and a national political force for African Americans after his groundbreaking election. He organized the 1972 National Black Political Convention in Gary and served as chairman of Jesse Jackson’s Democratic presidential campaign in 1984 and vice chairman four years later.

But his mayorship was also marred by the steel-producing city’s deterioration.

The election of Mr. Hatcher, then a 34-year-old activist, lawyer and city council president, sparked high emotions in Gary. He defeated incumbent A. Martin Katz in the primary by more than 2,300 votes, prompting a celebration that forced police to shut down a six-block section of the city for four hours.

The celebration was short-lived. When Mr. Hatcher refused to allow Lake County Democratic leaders to pick the city’s police chief, city attorney and other major positions in his administration, party Chairman John Krupa told Mr. Hatcher the party wouldn’t support him in the general election. Instead, the party threw its support to the Republican opponent, Joseph Radigan.

Gary hadn’t had a Republican mayor in almost 30 years, yet it was a difficult challenge for a campaign that had spent most of its money during the primary and now had no party to back it. Mr. Hatcher raised $8,000 to run full-page campaign ads in the New York Times and the Post-Tribune in Gary. The ad read, “Richard Hatcher is battling bigotry and ignorance. And he needs your help.”

The ads brought in more than $250,000, drew invitations to appear on TV and radio and attracted the attention of Sen. Robert F. Kennedy (D-N.Y.), Vice President Hubert H. Humphrey and others who held fundraisers.

“It was unbelievable,” Mr. Hatcher told the Associated Press in 2011. “We ended up having enough money to run a decent campaign.”

He gave credit for his election to the city’s black residents, who made up slightly more than half the city’s population of about 175,000 in 1967 but trailed whites in the number of registered voters.

“There was a tremendous spirit in the city and the black community was very united,” he said. “I think I received about 7 percent of the white vote. The other white candidates divided up the white vote, they really split it, which made it possible for me to win.”

Mr. Hatcher attracted hundreds of millions of dollars in federal money to Gary in his 20 years in office, some of which was used to build low-cost housing and public housing units. He also got federal funds to pay for jobs training, repaved deteriorating streets and had regular garbage collection in many inner-city neighborhoods for the first time.

When he was elected, only two of the city’s department heads were African American. A decade later, 25 of the city’s 40 department heads, including the police and fire chiefs, were black.

As a member of the Gary City Council before he became mayor, Mr. Hatcher helped pass an open housing law to end a practice that forced black residents to live primarily in the city’s midtown section because of restrictive property covenants.

Still, he couldn’t stop the city’s decline, which coincided with that of the U.S. steel industry. The company town, founded in 1906 by U.S. Steel Chairman Elbert H. Gary, had flourished as the industry did.

But while Mr. Hatcher was in office, U.S. Steel cut its workforce, and many white residents and businesses moved to the suburbs. Crime increased, and by 1984, Gary had the nation’s highest per-capita homicide rate.

By the time Mr. Hatcher left office in 1987, losing in the primary election, the city’s population had fallen by 50,000 residents to about 125,000. Gary’s current population is 76,000.

Richard Gordon Hatcher was born July 10, 1933, in Michigan City, Ind. He was one of 13 children, whose father molded railroad car wheels and whose mother was a factory worker. He graduated from Indiana University, earned a law degree from Valparaiso University in Indiana and moved to Gary after becoming a deputy prosecutor.

Survivors include his wife of 43 years, the former Ruthellyn Rowles, and three daughters.

“The thing I can say I am most proud of,” he said in 2011, “is the way the people of Gary have continued to persist in their efforts to create a better city for their children and for themselves.”

— Associated Press