Led Zeppelin’s origins can be traced back to the seminal British blues-rock outfit The Yardbirds. Guitarist Jimmy Page joined the group as a replacement bassist in 1966, soon switching to second lead guitar alongside Jeff Beck. This lineup was fleeting. Beck departed later that year, and The Yardbirds ran out of steam. Page hatched plans to form a supergroup, reuniting with Beck on guitars with the proposed addition of The Who’s Keith Moon and John Entwhistle. This dream group never materialized, though Page, Beck and Moon did collaborate on 1966’s “Beck’s Bolero”. This pivotal session marked Page’s introduction to bassist/keyboardist John Paul Jones.

The final New Yardbirds was far different than Page originally envisioned. First choice vocalist Terry Reid declined but recommended Robert Plant, an unknown singer from Birmingham. Plant, in turn, brought drummer pal John Bonham aboard. John Paul Jones was eager to collaborate again with Page. Page, still without a bassist, recalled Jones, and the lineup for the New Yardbirds was complete. The most popular anecdote of the band’s re-naming has Keith Moon and John Entwistle joking that any supergroup containing themselves and Page would go over like a lead balloon. The name stuck through the early lineup changes, but without the “a” in Lead at the suggestion of their manager, Peter Grant, to prevent “thick Americans” from pronouncing it as “leed”. Grant secured a $200,000 advance from Atlantic Records in November 1968, an astronomical sum for a new band. Led Zeppelin made their live debut at the University of Surrey, Guildford on October 15, 1968. The group’s eponymous first album was released early the following year, one of the pivotal records in the evolution of hard rock.

Official Website
BBC News: The Legend of Led Zeppelin
1971 interview with Robert Plant
Excerpt of Led Zeppelin 1968-1980: The Story Of A Band And Their Music