SHOWTIME

From left: Randy Meisner, Glenn Frey, Don Henley, Joe Walsh, and Don Felder.

By Sarah Rodman Globe Staff

When the Eagles were inducted into the Rock and Roll Hall of Fame in 1998, Glenn Frey addressed the speculation that the band responsible for one of the best-selling albums in US history was one that had been riddled with contention.

“We got along fine,” declared Frey, “we just disagreed a lot.”

Or he did anyway, according to a superb, new two-part documentary, “History of the Eagles,” airing Friday and Saturday at 8 p.m. on Showtime.

We will stop right here to say that if you are a fervent detester of the band — one of the most polarizing in rock — nothing in this documentary will change your mind, so move along and take it easy.

But if you fell under the sway of the Eagles’ beguiling country-rock hybrid, brimming with pristine harmonies and eminently singable melodies, you’ll want to settle in for the long run.

How revelatory the three hours, directed by Alison Ellwood and produced by Academy Award winner Alex Gibney (“Taxi to the Dark Side”), are will depend on the viewer’s level of fandom.

The first part of the doc — chock full of excellent archival footage — chronicles their rise in an LA scene that included friends and collaborators like Linda Ronstadt and Jackson Browne, their wild “third encore” bacchanals (with lines on mirrors and terminally pretty companions), the making of the classic “Hotel California” album, and their eventual implosion in 1980 after a fight that simmered onstage boiled over and off of it.

The second part briefly touches on Frey and Don Henley’s solo careers, and then picks up steam with the band’s reunion in 1994, up through the recording of their first new album in 28 years, 2007’s multiplatinum “Long Road Out of Eden.”