During the classic days of Deep Purple, Glover used Marshall Major stacks to get his famous grinding tone. We can see the amps behind Roger at 2:10.

In 1971 Deep Purple recorded his album "Machine Head" (edited in 1972). At some point, guitarist Ritchie Blackmore said he was to tired to record rhythm guitars, so Jon Lord decided to emulate it himself. For doing that, he conected Hammond organ to distorted Ritchie's amplifiers (Marshall Major at this time), and developed what he called "The Beast", one of his caracteristic sounds.

In this interview, Steve Rothery says, "In the old days, we’re going back a few years, from our second album, Fugazi, through pretty much to probably Radiation, the two amps I used were a Marshall master volume head on a 4x12 for the crunch sounds, sort of heavy chordal sounds, and a [Roland] JC 120 which I used with various effects: digital delays, BOSS chorus, BOSS DS-1 distortion for solo sound…"

In his old band Elf Dio used to play Bass through a Marshall Major head and stacks.

This head was later put up for auction in September 13, 2017, the Head was estimated at $10,000-$15,000 with a winning bid of only $3,200.

The description for this item read:

A 1972 Marshall Major 200-watt amplifier played by Ronnie James Dio, as the bassist for the band Elf, in the early 1970s. Affixed to the front with an England sticker and bearing various retailer's and service technician's stamps as well as several custom adhesive labels. Serial number A 3357D. The rare Marshall Major model was also notably used by guitarist Ritchie Blackmore, whose band, Rainbow, Dio would join a few years later.

10 1/2 by 29 by 11 inches

"With Rainbow for...Long Live Rock and Roll album I used...one of Ritchie's doctored 200W Marshall heads..."

in this performance bruce is standing in front of a marshall amp cab and amp head

Tom states he owns "six Marshall Majors" in the linked interview

"Live, I play though an Orange rig, but the amp I like to record with is a 1971 Marshall Major head. It’s the best sounding amp I’ve ever played through. I don’t know why more people didn’t get into them. It’s a 200-watt head, so maybe it’s that guitar players can’t get them to break up very easily. But with bass it sounds perfect. It gets pretty gnarly, but it stays smooth. It’s almost like naturally compressed sound."

You can see two Marshall Major full stacks in the background at 2:21 that I assume Michael Schenker lended to him

At least one of the 4 input Marshall's Manny Charlton during the early years of "Nazareth" was a 1971 Marshall Major (the other was likely a Super Lead of the same year, 1971). Built specifically for him and the band by Marshall and shipped out with the band's name printed out with a label maker as Marshall used in those days on the rear of the amps. Manny was turned onto Majors by Ritchie Blackmore. The amp has survived in its original condition to this day in 2023, now living with its third owner since Manny Charlton who sold the amp to a private collector in Texas where he lived at the time. The amp was then bought by another private collector from New Hampshire who in 2022 sold it to a musician in Massachusetts. This 1971 Marshall Major was bought and sold each time since the first private collector in Texas (who had a MASSIVE collection of vintage Marshall's and other amps) with a 1971 Super Lead which is likely to also have been one of the original Marshall's shipped to Nazareth and which belonged to Charlton. Unfortunately that cannot as of now be definitively confirmed as the first collector in Texas could not be sure which of the several 71 Super Leads he had and sold were Charlton's as none still had the original labels from the Marshall factory.

In the article titled "Mike Plotnikoff: How To Record Electric Guitars" from Sound On Sound, Mike Plotnikoff confirms using the Marshall Major head.

In the SoundCloud set "Songs from Tomorrow is Yesterday" by The Arcana, Peter Lennodo is seen using a Marshall Major guitar amplifier head.