Thus did Mike Bongiorno define them at Sanremo, in 1966. By literally translating the name of the band to "yard birds," he aimed to make the well-dressed and stiff audience at the festival smile, referring to them, by extension, as "Gallinacci," given that they could hardly speak a word of Italian... He, may his soul rest in peace, was unaware that "Yardbird" was the slang term for "inmate" but also for "grunt soldier."
Oh well...

Here we are still in the heroic era of blues orthodoxy... Clapton just a step away from John Mayall's Bluesbreakers...

The Yardbirds with Eric Clapton- "Louise/I Wish You Would" Live 1964 [Reelin' In The Years Archives]