On May 16, 1975, Junko Tabei became the first woman to stand on the summit of Mout Everest. (Anonymous/ASSOCIATED PRESS)

Junko Tabei, a Japanese mountaineer who became the first woman to reach the world’s highest peak when she climbed Mount Everest in 1975 and who scaled the tallest mountains in more than 70 countries, died Oct. 20 at a hospital near Tokyo. She was 77.

The cause was stomach cancer, her family said on her website.

Ms. Tabei, who became fascinated with climbing as a child, battled cultural norms throughout her life as she completed a decades-long quest in 1992 by reaching the top of the “Seven Summits,” or the highest peak on each continent.

But it was her determined effort to ascend the world’s highest mountain that cemented her reputation as one of the world’s most notable alpinists, male or female. She spent years preparing for her Everest expedition, financing much of it through her work as a technical editor and by giving piano lessons and teaching English.

Ms. Tabei defied the expectations of traditional Japanese society as she organized an all-female team of climbers. As she journeyed to the Himalayas in Nepal, she left her 3-year-old daughter at home with her husband in suburban Tokyo.

Mountain climber Junko Tabei in 2003. (Kazuhiro Nogi/AFP/Getty Images)

“When we asked for financial support for our expedition, I was told many times, ‘Women shouldn’t be climbing Everest,’ ” she recalled in a 2003 interview with Agence France-Presse. “They told me bluntly, ‘Forget about climbing. Rather than that, why don’t you just take care of your kids?’ ”

Ms. Tabei eventually obtained financing from a Japanese newspaper and television network, which ultimately led to conflicts on the trail.

On May 4, 1975, she and her team were sleeping in their tents, at an altitude of more than 21,000 feet, when they were jolted awake by an avalanche. Ms. Tabei was partially covered in snow and lost consciousness before Sherpa guides pulled her to safety by her ankles.

“As soon as I knew everyone was alive,” she told Sports Illustrated in 1996, “I was determined to continue.”

Male journalists chronicling the trek wanted to turn back, and Ms. Tabei had to pull rank to continue.

“If you climb with men, there are so many troubles,” Ms. Tabei told The Washington Post in 1991. “I had to say, ‘I am the leader, and I determine that — even if you are the sponsor.’ I wanted to concentrate on climbing, and here I had to worry about these other issues. Since then, I haven’t had sponsors. I’m much happier.”

Despite injuries to her back and legs, the 4-foot-10 Ms. Tabei forged up the mountain, sometimes on her hands and knees, before reaching the summit of Everest — 29,029 feet high — on May 16, 1975. She unfurled a Japanese flag and stayed at the top of the world for 50 minutes before beginning her descent, which was as treacherous as the climb.

Junko Tabei at a ceremony in Kathmandu, Nepal, in 2003. (Binod Joshi/AP)

Twenty-two years after Everest was first scaled in 1953 by Edmund Hillary of New Zealand and Sherpa guide Tenzing Norgay, Ms. Tabei became the first woman to accomplish the feat. It wasn’t until 1988 that an American woman, Stacy Allison, would complete an ascent of Everest.

Ms. Tabei continued her mountaineering expeditions around the globe for decades. After Everest, she climbed Africa’s highest peak, Mount Kilimanjaro in Tanzania, in 1980. She reached the summit of Aconcagua in Argentina in 1987, followed a year later by Mount McKinley (now Denali) in Alaska. She scaled Europe’s tallest peak, Mount Elbrus in Russia, in 1989.

In 1991, she climbed Antarctica’s Vinson Massif, then finished the last of the Seven Summits in 1992 by ascending Carstensz Pyramid (also known as Puncak Jaya) in Indonesia.

Over the years, Ms. Tabei climbed many of the world’s most storied mountains, including Annapurna in Nepal and Mont Blanc in the French Alps, and stood at the highest point of more than 70 countries.

“The winds never calm down just because women are climbing,” she said in 2003. “Nature’s conditions are the same for everybody.”

Junko Ishibashi was born Sept. 22, 1939, in Miharu, Japan. Her father was a printer.

She climbed her first mountains as part of a school outing when she was 10. She graduated in 1962 from Tokyo’s Showa Women’s University as an English literature major. She met her husband, Masanobu Tabei, while climbing a Japanese mountain in 1965, and they were married a year later. He survives, along with their two children.

Ms. Tabei worked as an editor for a scientific journal and, in 1969, founded a women’s climbing society.

She traveled often to Nepal, where she was honored for her mountaineering exploits, but she became a strong critic of crowded conditions on Everest and the commercialization of climbing. She thought, for reasons of safety and environmental preservation, that only a few well-managed groups should be allowed on the mountain each year.

“Climbing the mountain,” she said, “is its own reward.”

In 1994, Ms. Tabei was able to install a garbage incinerator at an Everest base camp to consume trash left by trekkers. She received a master’s degree in comparative social culture in 2000 from Japan’s Kyushu University, with a concentration on the ecological toll on Everest.

In her later years, Ms. Tabei led an annual trip by high school students to the summit of Japan’s highest peak, Mount Fuji. She continued to scale mountains around the world until last year, adding the highest spots in Luxembourg, Belgium and Niger to her personal list.

“Life is not forever,” she told The Post in 1991. “I don’t think people should leave behind a fortune, or things. When I die, I want to look back and know that my life was interesting.”