Glen Campbell, the country music icon who had multiple hits in the 1960s and 1970s, has died, as TMZ reports. Campbell had been battling Alzheimer’s disease. He was 81. Campbell let the public know about his battle with Alzheimer’s in 2011. He then embarked on a final tour, which ended in 2012. This period was documented in the 2014 documentary Glen Campbell: I’ll Be Me. The film featured the last song Campbell recorded, “I’m Not Gonna Miss You,” which was written about Campbell’s struggle with Alzheimer’s. His final album, Adiós, came out earlier this year; it was recorded in 2013.

Campbell, an Arkansas native, got his start as a guitarist in Los Angeles as part of the hit-making session musician collective, the Wrecking Crew (alongside artists including Leon Russell and Dr. John). He was briefly a member of the Champs after they scored a hit with “Tequila.” For a short period, he was also a touring member of the Beach Boys, filling in on bass and vocals for Brian Wilson. He appeared on Pet Sounds.

When he made the transition from session musician to solo artist, Campbell became a star. Hits like “Wichita Lineman,” “Rhinestone Cowboy,” and “Galveston” bridged the gap between country and mainstream pop. From 1969 to 1972, he hosted his own musical variety show called “The Glen Campbell Goodtime Hour.” Around that time, he also did some acting—he appeared in the 1969 John Wayne film True Grit, for example.

Meet Glen Campbell, released in 2008, featured the country legend covering the Replacements, the Velvet Underground, Jackson Browne’s “These Days” (made famous by Nico), the Foo Fighters, and more. His 2011 album Ghost on the Canvas featured contributions from Robert Pollard, Paul Westerberg, Billy Corgan, and many others. In 2013, Campbell released See You There, an album featuring stripped down versions of his hits.