Richardson Dilworth was a Pittsburgh-born lawyer who adopted Philadelphia as his home and fought as a Marine in World War I, earning a Purple Heart. He reenlisted at age 43 to fight in World War II and was awarded the Silver Star for bravery at Guadalcanal.

That alone would be a remarkable life, but Dilworth had political aspirations.

He and reform ally Joseph S. Clark ended nearly seven decades of Republican rule when they were elected district attorney and mayor, respectively, in 1951. After Clark was elected to the U.S. Senate, Dilworth took over as mayor in 1956 and held that office until 1962, when he stepped down to run unsuccessfully for Pennsylvania governor.

Before his death in 1974, Dilworth served for six years as president of the newly formed Philadelphia Board of Education.

On Thursday, the city celebrated the grand opening of the revamped Dilworth Plaza - rechristened Dilworth Park - on the west side of City Hall.

It was fitting that his name was retained for the dramatically transformed civic space. Besides reforming city government, Dilworth changed the city's landscape, most notably in the rebirth of Society Hill.

As mayor, he famously built a new house on Washington Square to demonstrate his commitment to revitalizing the colonial core of the city, which had been allowed to decline drastically.

Peter Binzen, coauthor with his son Jonathan of the just-published Richardson Dilworth: Last of the Bare-Knuckled Aristocrats, wrote that city planner Edmund N. Bacon in 1947 had put forth the idea of restoring Society Hill, which at that time was a slum of "seedy boardinghouses, rat-infested warehouses and vacant lots littered with trash."

It wasn't until Dilworth was mayor that the proposal became a reality.

Bacon was "the one that came up with the idea for Society Hill, and Dilworth pulled it off," Binzen said in an interview.

The renewal of Society Hill led eventually to the renaissance of Center City.

Dilworth also was an ardent advocate for public transportation and pushed hard to have the government buy out the privately held transit company that ran the buses, trolleys, and subways in Philadelphia.

His vision became a reality with the creation of SEPTA in the 1960s.

Some of his ideas never came to fruition. He foresaw a day when automobile traffic would be banned in Center City. He wanted to see City Hall torn down.

His public service continued after he left the mayor's office and he continued to be a dominant figure in city affairs.

Dilworth was appointed president of the city's Board of Education. In stark contrast to the current financial woes of Philadelphia's public schools, the district under Dilworth hired 3,000 new teachers, Binzen said.

But the societal upheavals of the 1960s hit the city hard and the backlash election of archrival Frank Rizzo as mayor in 1971 led Dilworth to step down from the board.

Dilworth Plaza was dedicated in 1977, but it was not designed with him in mind. It was named for Dilworth by City Council as an honor before he died at the age of 75.

"It was an abysmal space to begin with originally," said Crawford Hill, Dilworth's stepgrandson. "And there was no effort to incorporate the family in any meaningful way."

The dedication, he recalled, "was unfortunately sort of a nonevent."

Over the years, the bleak granite plaza became known as a magnet for the homeless and skateboarders. Before it was closed in 2011 for renovations, it was the site of the Occupy Philadelphia encampment.

Hill said he was pleased with the new Dilworth Park.

"It's exciting for the city," he said, "and will honor [Dilworth's] legacy."