Rep. Elijah E. Cummings (D-Md.) pondered his future in the late summer of 2015 as he stood on the steps of the House, where the Democrat had represented Baltimore for almost 20 years in relative anonymity. As a family of tourists approached, Cummings was certain it would be a case of mistaken identity.

“Who do you think I am?” he called out.

“Elijah Cummings, of Baltimore,” they responded.

He rushed down to shake their hands and apologize, explaining that strangers usually thought he was Rep. John Lewis (D-Ga.), the civil rights icon and fellow African American who also sports a shaved, bald head.

No longer in the shadows of other giants, Cummings had emerged as a powerful voice at home in West Baltimore, where he served as peacemaker during riots that followed police violence that spring. In Congress, he had risen to the role of top Democrat defending President Barack Obama from nettlesome GOP oversight investigations.

Over the next four years, after deciding to stay in the House, Cummings became a force of nature. After his elevation to chairman of the Oversight and Reform Committee, his investigations put the fear of political death in administration officials.

“I can’t tell you how many friends would call me and be in fear because they got a letter from Cummings. But he was a man of fairness,” Minority Leader Kevin McCarthy (R-Calif.) said Thursday during tributes on the House floor after Cummings died Thursday morning.

Even President Trump saw Cummings as a rival, particularly after he started investigations that examined how migrant children were being treated at the border. On a Saturday morning in late July the president launched into a Twitter attack against Cummings, against Baltimore, that was filled with venom.

Already ailing, Cummings appeared a week later at a park opening in Baltimore where he called on his constituents to embrace hope for their city and ignore the presidential harassment. “It gives people light — it brings light into their lives. I have so much to do,” Cummings said.

The lawmaker at that moment had completed a life story that seems like a political fairy tale in a Congress dominated by career politicians and family dynasties.

His parents were sharecroppers in South Carolina, toiling on the same land where their ancestors had served as slaves. In the 1940s, they moved to Baltimore and raised seven children, sending young Elijah to special-education classes because he struggled in elementary school.

About 60 years later — after becoming an honors student at Howard University, serving 14 years in the Maryland General Assembly, winning a special election in 1996 to the U.S. House — Cummings could scare the president of the United States.

But Cummings knew that alliances and respect from rivals would only make him more powerful. So his friendships and associations ranged from Rep. Mark Meadows (R-N.C.), the founder of the conservative House Freedom Caucus, to Sen. Elizabeth Warren (D-Mass.), a leading candidate for the 2020 presidential nomination who worked with him on the opioid crisis and income inequality.

Battling ligament issues the past two years, which led to an infection during one hospitalization, Cummings usually steered his walker to a seat in the front row of the House chamber, where the Congressional Black Caucus usually holds court.

On Thursday, as McCarthy, House Speaker Nancy Pelosi (D-Calif.) and others paid tribute, that seat was filled with white hydrangeas and white roses. Lawmakers huddled at his seat and hugged during votes, whispering to one another about what Congress had lost.

“It lost civility, it lost a degree of civility,” Lewis said in an interview after votes. “It lost a greater sense of hope and optimism. Elijah Cummings was one of the most hopeful, one of the most optimistic individuals I ever met.”

He never ran for an elected leadership position, but Cummings achieved a profile that few members of the Congressional Black Caucus have ever reached. His booming voice could instill fear among those meeting him for the first time.

“I’m going to ask you plainly,” Cummings told Rep. Alexandria Ocasio-Cortez (D-N.Y.) when they first met. “Are you here to do the work?”

The 29-year-old political celebrity had millions following her social media posts on everything from domestic policy to cooking. As she recounted in a series of Twitter posts, on that day Trump attacked Baltimore, Ocasio-Cortez promised she would.

He supported her for a seat on his committee and early on she repaid him with some of the best questioning of witnesses. “You want to be on his team,” she wrote.

In late February, Cummings faced his first big test as chairman during a hearing with the president’s former lawyer, Michael Cohen. The blockbuster hearing got live national coverage as Cohen testified about payments to buy the silence of Trump’s alleged mistresses and his racist behavior.

Meadows had an African American woman who worked for the Trump Organization and the Department of Housing and Urban Development stand behind him as a prop to demonstrate some black support for the president.

Rep. Rashida Tlaib (D-Mich.), a freshman, called it a “racist” act, and Meadows demanded an apology. The entire hearing, a success for Democrats to that point, was about to go off the rails, until Cummings stepped in and negotiated the peace.

The next day, Meadows approached Tlaib on the floor. They talked and embraced.

“He would always just calm the waters,” Pelosi recalled Thursday.

Lewis said Thursday that as Cummings’s stature grew, he was on the other end of the mistaken identity. On a recent flight from Atlanta to Washington, a former senator stopped by Lewis’s flight seat.

“Hello, Elijah,” he told Lewis.

In 2015, after Barbara A. Mikulski (D-Md.) announced she would retire from the Senate in 2016, Cummings faced pressure to run for the seat, particularly after the riots in Baltimore.

Maryland had never elected a black senator, and Cummings had a good sense of his chances to win. But he sometimes responded to inquiries by asking whether someone knew the average life expectancy of a black man in America.

It was about 69 years old, the age Cummings would have turned in January.

Instead, he stayed in the House and became more powerful than most senators.

In one of his final prominent speeches, three weeks after Trump’s Twitter outburst, Cummings connected today’s hate-filled rhetoric to the mass shootings in El Paso and Dayton, Ohio, a couple of days before, calling on Congress to do better.

“God has called me to this moment,” Cummings said. “I did not ask for it.”