Larry Hagman, the actor best known as the ruthless oilman J.R. Ewing on TV’s Dallas, died Friday afternoon. He was 81.

Members of his family said Hagman died of complications stemming from his recent battle with cancer. “Larry was back in his beloved Dallas, re-enacting the iconic role he loved most,” the family said in a statement. “Larry’s family and close friends had joined him in Dallas for the Thanksgiving holiday. When he passed, he was surrounded by loved ones. It was a peaceful passing, just as he had wished for. The family requests privacy at this time.”

TNT, which airs the current version of Dallas, issued the following statement: “All of us at TNT are deeply saddened at the news of Larry Hagman’s passing. He was a wonderful human being and an extremely gifted actor. We will be forever thankful that a whole new generation of people got to know and appreciate Larry through his performance as J.R. Ewing. Our thoughts and prayers are with his family at this very difficult time.”

Added Dallas studio Warner Bros. and executive producers Cynthia Cidre and Michael M. Robin, and the show’s cast and crew: “Larry Hagman was a giant, a larger-than-life personality whose iconic performance as J.R. Ewing will endure as one of the most indelible in entertainment history. He truly loved portraying this globally recognized character, and he leaves a legacy of entertainment, generosity and grace. Everyone at Warner Bros. and in the Dallas family is deeply saddened by Larry’s passing, and our thoughts are with his family and dear friends during this difficult time.”

Born to fabled actress Mary Martin and district attorney Larry Hagman in Fort Worth, Tex., Hagman decided to follow in his mother’s footsteps after attending New York’s Bard College — first by appearing in regional theater and then by moving to England to join the cast of his mom’s stage musical, South Pacific. After a tour of duty with the U.S. Air Force (he met his wife, Maj Axelsson, while stationed in England), Hagman returned to New York to perform on Broadway.

The small screen soon beckoned. He made guest appearances on shows like The ALCOA Hour, followed by a two-year stint on the New York-based daytime soap The Edge of Night. His first breakout role came in 1965 when he was recruited to play an amiable astronaut who falls in love with a bottle-dwelling genie in the NBC sitcom I Dream of Jeannie. But he cemented his position as a Hollywood superstar 12 years later by joining CBS’ Dallas. For 14 years, Hagman played the love-him-or-hate-him millionaire J.R.Ewing. The popular show’s infamous Nov. 21, 1980 episode — resolving the previous season finale’s “Who shot J.R.?” cliffhanger — remains the second-highest-rated TV show in history.

Behind the scenes, however, Hagman struggled for years with chronic alcoholism — so much so that a doctor told him in 1995 that he’d have to replace his liver or he’d be dead in six months. “In the heyday of Dallas, it got to the point where I showed up for work about 6:30 in the morning, and by around 9, I might have opened a bottle of champagne, which I would nurse until about noon,” Hagman told People in 1995. “By lunch I might start on another half-bottle of champagne. I would go through about three bottles a day, sometimes with people who would drop by the set, but mostly by myself. I just kept that steady drip going. The drinking sometimes made it harder to remember lines, but I liked that constant feeling of being mildly loaded.” Thanks to the 16-hour liver transplant surgery, Hagman said his doctors “saved his life.” A year later, he served as the national spokesman for the 1996 U.S. Transplant Games and continued to serve as an advocate of organ donation and transplantation until his death. Despite occasional acting roles after Dallas left the air in 1991 (in the 1998 film Primary Colors and a five-episode arc on Nip/Tuck in 2006), Hagman largely withdrew from the limelight.

Then, last summer, TNT rebooted Dallas last summer, with Hagman on board. The rest of the cast included other original cast members as well, along with a new generation of the Ewing clan. But last October Hagman announced he was diagnosed with cancer, and said he hoped to continue in his role on the show’s second season.

“As J.R. I could get away with anything — bribery, blackmail and adultery,” Hagman said at the time in a statement.

“But I got caught by cancer. I do want everyone to know that it is a very common and treatable form of cancer. I will be receiving treatment while working on the new Dallas series. I could not think of a better place to be than working on a show I love, with people I love. Besides, as we all know, you can’t keep J.R. down!”

According to the Dallas Morning News, in addition to his wife, Mr. Hagman is survived by a daughter, Kristina Hagman, a son, Preston Hagman, and five granddaughters.