Thirty-six years after she last took aim with her AK-47 assault rifle, Ngo Thi Thuong’s phone rang.

Gen. Vo Nguyen Giap, who had led the North Vietnamese military during the Vietnam War, was looking for the woman who had shot down an American bomber in June 1968. In the nearly four decades that had passed, she had worked many jobs and raised three children. Few people outside her family had heard her wartime stories.

Heroines and striking female figures are not new in Vietnam — they have played an integral role in Vietnamese history for millenniums. In the 1st century A.D., the Trung sisters, often called Vietnam’s earliest national patriots, led a three-year rebellion against the Chinese Han dynasty, which ruled their country. The female legacy persists in the modern era; in all of Vietnam’s recent conflicts, women have been crucial. They fought alongside men and carried heavy loads down the Ho Chi Minh Trail.

Yet as the historian Karen G. Turner notes in her book “Even the Women Must Fight,” “Women warriors, so essential to Vietnam’s long history and so important in the most photographed war in history, have remained invisible.”

The following are stories from women who were all soldiers for the North Vietnamese Army in the war against the United States. Most were young when they joined — teenagers, barely out of school or too poor to attend in the first place. Some had seen war already, yet still had no idea what they would find this time around. For a few, motherhood came before they fought, while for others, it was not until after they returned home.