Mr. Johnson, who represented a district near Dallas that included the growing city of Plano in Collin County, was the oldest member of Congress when he retired in 2019.
He was considered one of the most conservative members of the House of Representatives and helped found the Conservative Action Team, a group that later became the influential Republican Study Committee. He was a member of the tax-writing House Ways and Means Committee and a staunch supporter of the military. He helped pass the Military Family Tax Relief Act of 2003, which reduced taxes and increased death benefits for the families of service members.
Although few major legislative initiatives bore his name, Mr. Johnson drew his political and moral authority from his experiences as a combat veteran of two wars and as a prisoner subjected to brutal treatment after being shot down over North Vietnam in 1966.
By all accounts, Mr. Johnson was a superb fighter pilot who flew 62 missions during the Korean War, shooting down one enemy plane in aerial combat. He was a member of the elite Thunderbirds aerobatic team and later directed what is now the Air Force Weapons School.
“I had spent hundreds of hours teaching and practicing the tactics of dogfighting,” he wrote in a 1992 memoir, “Captive Warriors: A Vietnam POW’s Story.” “It was what I did best. I liked seeing the enemy — battling against another pilot eye to eye.”
In Vietnam, Mr. Johnson was flying his 25th mission when his F-4 Phantom fighter-bomber was shot down on April 16, 1966. His injuries included a broken arm, a broken back and a dislocated shoulder, none of which was properly treated during his imprisonment.
He was taken to Hanoi’s Hoa Lo, derisively known to U.S. prisoners as the Hanoi Hilton. He was alternately questioned and tortured from the beginning.
When he asked to use the toilet, he wrote, “The guard scowled fiercely, walked out and returned in a moment with a paint can so rusted that it crumbled when my hand touched it. It was to be the only toilet facility I would have for the next five years.”
Mr. Johnson concealed notes to his fellow prisoners in the can and learned to communicate through a coded system of tapping on walls. He was one of several POWs, including Jeremiah A. Denton Jr., a future Republican senator from Alabama, singled out for particularly harsh treatment for defying their North Vietnamese captors.
“They put me in the cell right next to him,” Mr. Johnson recalled at Denton’s funeral in 2014. “All I heard was this banging on the wall. He yelled, ‘I’ll teach you the tap code. Just pay attention.’ ”
They were among a group of 11 prisoners moved to a remote facility they called Alcatraz. For 42 months, Mr. Johnson was held in solitary confinement, often locked in leg stocks, preventing him from moving. Guards twisted his broken right arm and then pulled on his dislocated left shoulder until both arms were together behind his back.
“I could not believe a body could endure such excruciating pain and remain conscious,” he wrote.
He subsisted on meager rations of rice and pork fat — often with the pig’s skin and bristly hair — and weeds.
It took two years before his wife and children learned that he was alive and held as a prisoner of war.
For the last 18 months of his captivity, Mr. Johnson shared a cell with John McCain, a Navy pilot who had been shot down in 1967. McCain, a long-serving senator from Arizona, was the Republican nominee for president in 2008.
Mr. Johnson weighed 120 pounds when he was released Feb. 12, 1973. His right hand was permanently disabled, and he walked with a limp for the rest of his life.
Samuel Robert Johnson was born Oct. 11, 1930, in San Antonio. His father worked for an insurance company, and his mother managed a Western Union telegraph office. The family lived in Georgia for a few years before settling in Dallas.
Mr. Johnson, a 1951 graduate of Southern Methodist University in Dallas, was a member of the Air Force ROTC and decided to make the military his career.
He received a master’s degree in international affairs from George Washington University in 1974. His military decorations included two Silver Stars, two awards of the Legion of Merit, the Distinguished Flying Cross, the Bronze Star Medal and two Purple Hearts.
After retiring from the Air Force as a colonel in 1979, he settled in Plano and opened a home-building business. He was elected to the Texas state legislature in 1984, and then won his congressional seat through a special election in 1991. He was reelected 13 times in a solidly Republican district, often with little or no Democratic opposition. He did not seek reelection in 2018 and retired when his term ended in 2019.
Mr. Johnson was known for making strong and often controversial statements about patriotism. He likened President Bill Clinton to North Vietnamese leader Ho Chi Minh because Clinton had visited the Soviet Union as a college student.
In the 2000 Republican presidential campaign, he supported then-Texas Gov. George W. Bush, who did not serve in Vietnam, over McCain, his fellow POW.
“I happened to be with McCain for the last year and a half in a prison camp over there in Vietnam,” Mr. Johnson said at a campaign rally for Bush in South Carolina. “I know him pretty well . . . and I can tell you, he cannot hold a candle to George Bush.”
He disagreed with McCain’s drives to ban torture by U.S. interrogators, create more restrictive campaign-finance legislation and to normalize relations with Vietnam. Yet, in 2008, he endorsed McCain, saying that as a Republican, it was “time to get behind the front-runner.” (McCain died in 2018.)
In 2004, Mr. Johnson became an outspoken critic of Democratic president nominee John F. Kerry, who had received many of the same combat honors — Silver Star, Bronze Star, Purple Heart — as Mr. Johnson had in Vietnam.
Because Kerry turned against the war effort, Mr. Johnson labeled him “Hanoi John” and charged him with “nothing short of aiding and abetting the enemy.”
Mr. Johnson’s wife of 65 years, the former Shirley Melton, died in 2015. A son, James Robert “Bob” Johnson, died in 2013. Survivors include two daughters, Gini Johnson Mulligan and Beverly Johnson Briney; and 10 grandchildren.
Despite making contentious public statements, Mr. Johnson did not appear to hold grudges after Election Day.
He was on friendly terms with Ann Richards, Texas’s onetime Democratic governor, and even McCain.
“I wasn’t really as courageous as Sam Johnson,” McCain told the Dallas Morning News in 2003. “I mean that. He suffered a lot more than I did.”
Read more Washington Post obituaries: