Rana... David Pegg joind forces with Jethro Tull in 1979 after John Glasscock died... It was after one of the famous Fairport Convention break-ups, I'm pretty sure...
From the sources I've read, other than an interest in rural English life, Ian Anderson doesn't really have much in the way of 'folk roots'... he was first a classical guitar player and self-taught blues and jazz floutist... The rusticy phaze that Tull went through in the mid 70's was mostly the result of Ian finally having the money and moving to the country... Minstrel In The Gallery was sort of the beginning of it, and some say it peaked during Heavey Horses... the threads of rustic life stay in Ian's and Tull's music though through to present day...
check out http://www.cupofwonder.com/ It's one of THE Jethro Tull web sits out here...
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