"Bands, too, opened their purse strings to help the Monty Python team. Three of the biggest names in rock coughed up thousands for their second feature, Led Zeppelin forking out 31,500, Pink Floyd gifting 21,000, and Jethro Tull frontman Ian Anderson personally putting up 6,300 of his own money.

It was serious cash. Adjusted for inflation, it's a combined donation of over 761,900 in today's money.

Idle further discussed the musical funders on X, highlighting the little interest in visiting the locations due to filming in Scotland and jokes they still "couldn't afford horses", Led Zeppelin's Jimmy Page and Robert Plant did attend the film's London premiere in April '75."

more at the link... including George Harrison, who funded Life of Brian by remortgaging his home, compares his role in the Beatles to Eric Idle's in Python:

""Once I was moaning a little bit on Brian, saying, It was hard to get onscreen with Michael Palin and John Cleese.

He said, Well, imagine what it's like trying to get studio time with Lennon and McCartney.'

I said, All right. Absolutely. Got it. OK. Check. I'll shut up now.' Then it occurred to me that yes, in fact, we were slightly the outsiders, playing similar roles in our groups."