Bloodlines were so crucial to Van Halen's chemistry that it's hard to imagine the band being named anything else.

But they actually went by something slightly less subtle before Alex and Eddie Van Halen begrudgingly adopted their last names as a now-iconic moniker: Mammoth.

The brothers' journey to "Van Halen" began in the summer of 1969, when they recruited an older teenager, bassist Dennis Travis, to round out a group Eddie would playfully dub Trojan Rubber Company. Often featuring singer-guitarist Bill Maxwell, they were strictly a covers act at this stage, saluting rock giants like Jimi Hendrix and Cream.

Travis was key to the band's development, as Greg Renoff noted in his 2015 book Van Halen Rising. He showed Eddie the virtuosic Ten Years After track "I'm Going Home," which inspired some of Van Halen's early, lightning-fast guitar solos.

By around 1971, Trojan Rubber Company had evolved into Genesis, which featured Alex and Eddie with bassist Mark Stone. The trio, still in covers mode, developed a reputation for their loud and aggressive live shows.

"It seems that since [David Lee Roth] has been in the band, we got this rowdy and crazy brown cloud hanging over us," Eddie told Guitar World in 1985. "But we had it way before Dave was even in the band. Schools wouldn't hire us, [and] nobody wanted anything to do with us."

They couldn't stick with their name for obvious reasons, given that an innovative British prog-rock band had already claimed it. Eddie discovered that later in the year while browsing a bin at a local record store and pulling out a copy of Nursery Cryme.

After brainstorming some other ideas, they arrived at Mammoth – an accurate description of their enormous sound at local gigs.

"These backyard and house parties were what we did on weekends," classmate Dana MacDuff told Renoff. "These parties would all happen by word of mouth. You'd be at school and someone would say, 'Hey there's a party tonight at so-and-so's house. Mammoth's playing.' In fact, it seemed like literally every party we went to, Mammoth was playing. We saw them all the time. They were the party soundtrack, and we always knew it would be a good party if Mammoth was playing. You'd pay a buck or two to get in to pay for beer. There would be a hundred, two hundred or three hundred people there."

Of course, Mammoth wouldn't stick either: In mid- to late 1973, they received a cease-and-desist letter from a San Fernando group with the same name. But a new era deserved a clean start anyway: By 1974, they'd hired Roth as their frontman and brought on Michael Anthony to replace Stone.

Alex and Eddie wanted to rechristen the quartet Rat Salad — a nod to the Black Sabbath track of the same title. Roth, however, lobbied for Van Halen because of its inherent power.

The name, it turned out, perfectly matched their music.

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