He shot to fame as a member of a made-for-TV rock group, but he denied that he was the group’s only “real” musician. He went on to create some of the first music videos.Michael Nesmith, who rocketed to fame as the contemplative, wool-cap-wearing member of the Monkees in 1966, then went on to a diverse career that included making one of the rock era’s earliest music videos and winning the first Grammy Award for video, died on Friday at his home in Carmel Valley, Calif. He was 78.Jason Elzy, the head of public relations for Rhino Records, the label that represents the Monkees, said the cause was heart failure.Mr. Nesmith was a struggling 23-year-old singer and songwriter when he saw an advertisement in Variety seeking “4 insane boys” for “acting roles in new TV series.” Two aspiring television producers, Bob Rafelson and Bert Schneider, inspired by the Beatles’ movies, were hoping to make a TV series about the zany antics of a rock band — not a real rock band (although the Lovin’ Spoonful was briefly considered for the job), but actors with musical backgrounds who could create the illusion of a band.The four members were picked to fit types. Davy Jones, a British vocalist, was the cute scamp; Micky Dolenz, the drummer and primary lead singer, was the wild jokester; and Peter Tork, the bass player, was the lovable dim bulb. Mr. Nesmith, a guitarist and occasional singer, was variously described as the cerebral Monkee, the introspective Monkee, the sardonic Monkee, the quiet Monkee.“He has that dry Will Rogers sense of humor,” Mr. Dolenz told Rolling Stone in 2012, characterizing Mr. Nesmith’s real persona. “That’s probably one of the reasons they cast him.”The show made its debut in September 1966, and though it lasted only two seasons, the Monkees became a cultural reference point, thanks largely to their best-selling albums (which featured a lot of studio musicians and backup singers, especially early on). Mr. Nesmith, who wrote and produced some of the Monkees songs, had the reputation of being the only “real” musician in the group, but in his 2017 memoir, “Infinite Tuesday,” he disputed that.The four members of the Monkees were picked to fit types. Mr. Nesmith was variously described as the cerebral Monkee, the introspective Monkee, the sardonic Monkee, the quiet Monkee. NBC/via Getty Images“It would always seem wildly ironic to me that I was the one given credit in the press for being the ‘only musician’ in the Monkees,” he wrote. “Nothing was further from the truth.”The Monkees in action (or at least acting), from left: Davy Jones, Peter Tork, Micky Dolenz and Mr. Nesmith.Getty ImagesBut he was musician enough to have a modest solo career after Monkee mania faded at the end of the 1960s, and that led him into a role in music-television history.In 1977 he recorded a song called “Rio” for the Island Records label, which asked him to make some kind of promotional film for it.“They wanted me to stand in front of a microphone and sing,” Mr. Nesmith was quoted as saying in the 2011 book “I Want My MTV: The Uncensored Story of the Music Video Revolution,” by Craig Marks and Rob Tannenbaum. But he did something different.“I wrote a series of cinematic shots: me on a horse in a suit of light, me in a tux in front of a 1920s microphone, me in a Palm Beach suit dancing with a woman in a red dress, women with fruit on their head flying through the air with me,” he said. “As we edited these images,” he added, “an unusual thing started to emerge: The grammar of film, where images drove the narrative, shifted over to where the song drove the narrative, and it didn’t make any difference that the images were discontinuous. It was hyper-real. Even people who didn’t understand film, including me, could see this was a profound conceptual shift.”Almost by accident, he had made one of the first music videos as that term came to be understood. It got some play in Europe, but Mr. Nesmith was struck by the fact that there was no outlet in the United States for showing such works, which a few other pop and rock stars were also beginning to make (and some, like the Beatles, had made earlier).The Monkees (from left, Mr. Tork, Mr. Nesmith, Mr. Jones and Mr. Dolenz) in 1967, at the height of their fame.Ray Howard/Associated PressIn 1979 he and the director William Dear developed a TV show, “Popclips,” for Nickelodeon, a recently inaugurated channel for children that was looking to add teenagers to its audience. “Popclips” showed nothing but music videos, introduced by a V.J. The show is often said to have helped inspire the creation of MTV in 1981, although accounts of the various people who claim to have had a role in MTV’s emergence differ widely. Mr. Nesmith, in his interview for “I Want My MTV,” took a nuanced view of his role.“It’s a gradual coalescence of different things,” he said of the concept of a full-time music video channel, “a confluence of energies. It’s one of those ideas that nobody really thinks up. It’s like justice. Or kindness. Nobody thinks that up.”Robert Michael Nesmith was born on Dec. 30, 1942, in Houston. His father, Warren, and his mother, Bette (McMurray) Nesmith, divorced in 1946, soon after Warren returned from fighting in World War II. His mother later remarried, took the last name Graham and became wealthy from inventing Liquid Paper and running the company that produced it. That money would give Michael the financial security to follow his varied interests.His mother moved to Dallas, where he grew up. In his book, he described himself as an indifferent student in high school.In 1960 he enlisted in the Air Force (earning a high school equivalency diploma while in the military). The Air Force, though, was not a good fit, and he requested and received an early discharge in 1962.He enrolled at San Antonio College, where he began performing on a guitar he had received as a Christmas gift from his mother and stepfather in 1961. He also met a fellow student, Phyllis Barbour. In 1964 the newly married couple resettled in Los Angeles, where Mr. Nesmith sought to further his fledgling performing and songwriting career.Mr. Nesmith in the recording studio in an undated photo. When his days as a Monkee were over, he formed a country-rock band and became a pioneer of music video.Michael Ochs Archives/Getty ImagesAmong the songs he wrote in 1965 was “Different Drum,” though its best-known incarnation, a hit version by Linda Ronstadt and her group the Stone Poneys, would not come out until 1967, after the Monkees were famous. Mr. Nesmith was playing in local clubs and sometimes serving as M.C. at one of them, the Troubadour, when someone showed him the Variety ad.The Monkees’ early songs — provided mostly by outside writers and recorded largely by studio musicians, with the Monkees (primarily Mr. Dolenz and Mr. Jones) providing the vocals — were such hits that fans began clamoring to see the fake group live in concert.“We started wailing away in rehearsal, trying to get a decent rendition of the songs on the records,” Mr. Nesmith wrote. “It never sounded great, but it didn’t sound all that bad.”The Monkees gave their first live performance in December 1966 in Hawaii, the start of a tour that took them all over the United States.“The Monkees have been practicing more, and are learning to pull off live concerts,” The Boston Globe wrote in March 1967. “On their first tour, the continuous screaming drowned all imperfections in the music.”The mania, though, soon played itself out. “The Monkees” ended after two seasons, in March 1968, and both Mr. Tork and Mr. Nesmith left the band shortly afterward. Mr. Nesmith formed his own group, the First National Band, and released an album in early 1970, “Magnetic South,” which included a minor hit, “Joanne.”Two more First National Band albums quickly followed, showcasing a country-rock sound that was just slightly ahead of its time — as the First National Band was petering out in 1972, groups like the Eagles were pushing a similar sound into the mainstream, leaving Mr. Nesmith feeling as if he had missed the boat.Mr. Nesmith in concert with the Monkees in 2013, during one of the band’s periodic reunions.Jeff Daly/Invision, via Associated Press“I was like, ‘Why is this happening?’” he recalled in an interview with Rolling Stone in 2018, when he organized a modest “First National Band Redux” tour. “The Eagles now have the biggest-selling album of all time and mine is sitting in the closet of a closed record company?”Several other musical ventures followed, but Mr. Nesmith was growing increasingly interested in video. He thought that videodiscs, which had come on the market in the late 1970s, were the future of music, and after “Rio” and “Popclips” he made “Elephant Parts,” an hourlong disc of music videos and comedy sketches (including a parody of his own song “Joanne” that featured the Japanese movie monster Rodan instead of a woman).In 1982, “Elephant Parts” received the first Grammy Award for video, a category called video of the year at the time (soon to be split into short- and long-form awards, the first of several title changes as the art form and technology evolved).“Elephant Parts” led in 1985 to “Michael Nesmith in Television Parts,” a short-lived TV sketch show. Mr. Nesmith had also begun producing movies, most notably “Repo Man” in 1984.And he continued to be a Monkee — when it suited him. In varying combinations, Mr. Tork, Mr. Dolenz and Mr. Jones (until his death in 2012) toured and recorded periodically as the Monkees. Mr. Nesmith only occasionally joined them onstage, but all four played and sang on, and wrote songs for, the group’s 1996 album, “Justus.” In 2016 the group released the album “Good Times,” which included some archival material recorded by Mr. Jones.Mr. Nesmith also wrote and directed “Hey, Hey, It’s the Monkees,” a television special made to promote “Justus,” which was broadcast in early 1997.Mr. Nesmith became more willing, or perhaps more available, to embrace his Monkee past in recent years. He joined Mr. Tork and Mr. Dolenz for a tour after Mr. Jones’s death.Peter Tork died in 2019. Mr. Dolenz is now the last surviving Monkee.In 2018 Mr. Nesmith teamed with Mr. Dolenz for a tour, but that June he had to cancel the final four shows when shortness of breath left him unable to perform. He told Rolling Stone that he had quadruple bypass surgery shortly after that.“I was using the words ‘heart attack’ for a while,” he said. “But I’m told now that I didn’t have one. It was congestive heart failure.”Yet by that September he was back touring with his own group, playing his First National Band material. And he and Mr. Dolenz went back on the road this year, for what was billed as the Monkees’ farewell tour. They gave their last performance on Nov. 14 in Los Angeles.Mr. Nesmith’s first marriage ended in divorce in 1975. His marriages to Kathryn Bild, in 1976, and Victoria Kennedy, in 2000, also ended in divorce. He is survived by three children from his first marriage, Christian, Jonathan and Jessica Nesmith, and a son from a relationship with Nurit Wilde, Jason Nesmith, as well as two grandchildren.Mr. Nesmith’s varied career included a legal battle with PBS. Early in the video era, his company, Pacific Arts, had bought the home video rights to some of PBS’s most popular programs, including “Nature.” PBS sued him over royalties, but in 1999 a federal jury in Los Angeles found in Mr. Nesmith’s favor and awarded him $47 million. His reaction to his legal victory was typically wry.“It’s like catching your grandmother stealing your stereo,” he said after the verdict was issued. “You’re glad to get your stereo back, but you’re sad to find out that Grandma’s a thief.”Maia Coleman contributed reporting. More