I can claim to having first caught (Kennet) barbel on boilies in 1984, courtesy of Pete Springate and Kenny Hodder and particularly the nameless guy, a pal of theirs and mine, a genius carp-fisher, who stocked Colne Mere just as much as Pete and Kenny did. In 1983 I had helped him and his girlfriend spend several months in India fishing in my footsteps, and when they came back, penniless as I had been on return in the late 1970s, I said "Come and my live in my spare room in Old Windsor.". They did, stayed a year or so, and did he and I do some fishing, And did he do some bait-making in my kitchen (kitchen cupboards full of big jars and containers of Casein, Sodium Caseinate, Calcium Caseinate, Whey, semolina and food flavourings), for the water he was fishing completely alone then (Colne Mere) - boilies. Lots of boilies. I was barbelling (as well as trout and grayling flyfishing the upper waters of) the Kennet a lot at that time - with trout-pellet paste, meat paste, fish paste, corn very occasionally (it had blown several years earlier), meat, worm, maggots, casters and hemp superglued to 1lb mono (not hair-rigged but tied to the eye and twisted round a wide-gape hook).
"Why don't you try my bait for barbel?" he said one evening as he, his girlfriend and I sat in my little living room in front of a 'vid'.
I did and caught three fish, to eight pounds (Newbury area), then I moved to Wales in late 1986 and stopped barbelling for several years (salmon in Wales, more Indian mahseer, two trips after Goliath...) and never gave boilies for barbel another thought until the Roger Baker boom of the 1990s.
Full circle.
PS - Remember that south Indian fishers have been using rock-hard boiled and steamed paste baits (made from ragi millet flour) for hundreds and hundreds of years. We had both used them by the ton on the the Kaveri...