Kay Granger, the first Republican woman from Texas to be elected to Congress, who went on to chair the powerful House Appropriations Committee, died on Sunday at her home in Fort Worth. She was 83.

Her son J.D. Granger said the cause was Alzheimer’s disease.

Ms. Granger left Washington in 2024, during her final year in the House, and moved into an independent living facility in Fort Worth — an arrangement that her office did not disclose for months.

When a conservative website broke the news in December 2024, Ms. Granger’s son Brandon told The Dallas Morning News that she had been experiencing “dementia issues.” In a statement at the time, Ms. Granger said she had been navigating “unforeseen health challenges that have progressed since September and made travel to D.C. difficult.”

The news caused a stir in Washington, coming as several older members of Congress also faced health issues and the Republican majority in the House was razor-thin.

Ms. Granger was a local Republican official in Fort Worth and the city’s first female mayor before she was elected to Congress in 1996, when she won the seat once held by former Speaker Jim Wright, a Democrat. She served for nearly three decades and became the dean of the Texas delegation, the largest state delegation in the Republican conference.

She was a member of the Appropriations Committee for most of that time, rising to become the committee’s ranking Republican and, for about a year, its chairwoman.

A defense hawk, Ms. Granger steered lucrative contracts to the major defense manufacturers in her district, including Bell Helicopter and Lockheed Martin, which built the much-debated F-35 fighter jet there. She established a reputation as an influential defender of the F-35, saying the jet was critical to the nation’s national security despite its exorbitant price.

In October 2023, at 80, she announced she would not seek re-election in 2024, without specifying a reason. But her colleagues told reporters that as someone who had long favored robust spending on defense, she was frustrated by far-right Republicans who wanted to limit spending and focus on hot-button cultural issues.

In April 2024, Ms. Granger stepped down as Appropriations chairwoman. She said she wanted to give the committee time to make a seamless transition for the coming fiscal year.

She appeared at the Capitol in November 2024 for a ceremony honoring her tenure on the committee. The next month, The Dallas Express, a conservative website, reported that Ms. Granger had been residing in the independent living facility for several months. She had not voted in Washington since July.

While Ms. Granger had already announced her retirement, the news of her extended, unexplained absence from Washington reignited a debate over whether the House and Senate should impose term limits on their members. Over the years, Congress had become a sinecure for several septuagenarians and octogenarians, who were encouraged to stay in part by a seniority system that rewarded incumbency and longevity. But no new limits were established.

Norvell Kay Mullendore was born on Jan. 18, 1943, in Greenville, Texas, and grew up in Fort Worth. Her parents, Norvell and Alliene Mullendore, both teachers, divorced early, and Kay and her sister were raised by their mother.

Kay graduated from Texas Wesleyan University in 1965 with a teaching certificate and a bachelor’s degree in English and home economics. She was teaching high school when her husband, John Granger, whom she had married in 1964, left her with three small children.

“I was making $13,000 a year,” Ms. Granger told The Hill in 2008. “It’s the reason I talk so much to working mothers.”

She got a job selling commercial insurance from home, telling The Hill that “you just fight your way through the day.”

A workaholic, she expanded her business and opened a second office. At the same time, her mother, who had had a stroke, moved in with her and helped watch the children.

In addition to her two sons, Ms. Granger’s survivors include her daughter, Chelsea Elizabeth Granger, and five grandchildren. Her sister, Mary Lynn O’Day, died in 2020.

Ms. Granger gained some local notoriety when she successfully fought the building of a liquid waste disposal plant near her home. That led to an appointment on the Fort Worth zoning commission. She was elected to the City Council before becoming mayor in 1991.

Fort Worth faced one of the worst crime rates in the country at the time; she pushed through a tax increase to pay for more police and community centers and helped turn those numbers around.

As mayor, Ms. Granger was not affiliated with any political party and established a reputation as a pragmatist who got things done. When the congressional seat opened up, Democrats and Republicans both recruited her. A social moderate, she ran as a Republican, viewing the party as more fiscally responsible. In 1996, she was the first Republican elected from the 12th Congressional District.

She was known for her belief in maintaining a strong national defense. She defended the war in Iraq as the “battlefield” of a global war on terror, according to The Texas Tribune, and steadfastly supported Ukraine when Russia invaded in 2022.

With relatively progressive social views, Ms. Granger was under constant pressure from conservatives. She started out supporting abortion rights but later called for overturning Roe v. Wade.

She opposed Donald J. Trump for president in 2016, saying his comments about grabbing women were “disgusting” and faulting him for criticizing Senator John McCain’s war record. But in 2020, as she faced a primary challenge and critics said she was insufficiently supportive of Mr. Trump, she endorsed him. Mr. Trump in turn endorsed her, despite his belief that funding for the F-35 jets — her signature issue — should be cut drastically.