I was able to vote in the 75 referendum about remaining in the common market (that we had been taken into by Heath without electoral consent), and I remember all the assurances that it was purely a trade arrangement and there would be no loss of sovereignty. Even then, many were unhappy with the Common Market restrictive rules and that's how we got a referendum in '75. There wasn't any internet in those days to check out the treaties and so discover what lying b******* politicians were! We were wrong to trust politicians and it's gone downhill, if anything, since. Our country belongs to everyone, not just the politicians.
I reckon Heath was either blackmailed or bought. Maybe both, but we'll never know for sure.