Photographs documented US Sen. Dianne Feinstein's groundbreaking career in politics

U.S. Sen. Dianne Feinstein’s groundbreaking career in politics was documented in photos from the moment she was sworn in as San Francisco mayor in the aftermath of tragedy to her long-awaited return to the U.S. Senate after illness earlier this year.

The pictures start in black and white, showing a young Feinstein as she leads an estimated 15,000 marchers in memory of slain Mayor George Moscone and Supervisor Harvey Milk. She became the city’s first female mayor after their assassination in 1978 and held the office for nearly a decade.

As mayor, she helped secure millions of dollars from the federal government to refurbish the city’s iconic cable cars and took a celebratory ride with Tony Bennett, who famously crooned of leaving his heart in San Francisco.

The photos turn into color as Feinstein broke more barriers. She won a U.S. Senate race in 1992 to become one of California’s first two female senators. She was the first woman to head the Senate Intelligence Committee and the first woman to serve as the Judiciary Committee’s top Democrat.

She was the longest-tenured female senator in U.S. history and oldest sitting senator when she died Thursday at age 90 at her Washington, D.C., home.

Along the way, a playful Feinstein flexed a bicep in support of California Republican Gov. Arnold Schwarzenegger's $9 billion water bond for the state and linked arms with GOP President George W. Bush as they toured wildfire damage in San Diego. The centrist Democrat valued working with Republicans across the aisle.

One of her most significant legislative accomplishments came at the start of her career when the Senate approved her amendment to ban the manufacturing and sale of certain types of semi-automatic guns. The legislation expired a decade later, in 2014, and was never revived despite efforts by gun control advocates.

During debate on the ban, Idaho Republican Sen. Larry Craig suggested Feinstein study up on the issue of guns. ″Senator, I know something about what firearms can do,” she replied.

Feinstein’s lengthy career was marred by illness and frustration among fellow Democrats over her health. She returned to Capitol Hill in May after more than two months out while recovering from the shingles virus.

Tributes poured in Friday for Feinstein.