Speaking of which, after I mentioned The English Sunrise and its similarity to Unmitigated England (in a good way) Peter Ashley got in touch to say that he had worked with Tony Evans around that time and the book inspired him to go and do what he does now. He also pointed out that there's a book about Tony Evans called Taking His Time, which I have now purchased and can also recommend.
Tony Evans had an interesting career as a photographer working from the 60s to the early 90s, winning lots of awards for advertising and feature photography in the process - The English Sunrise won a D&AD Silver Award for Most Outstanding Book Photography in 1973. He worked for the Sunday Times and Radio Times in the 1970s, and on special issue postage stamps in the 1980s among other things. He died in 1992 and the book is full of very sweet testimonies from friends and colleagues. I couldn't find out much about him online but as soon as I opened the book I realised that I had seen his photographs everywhere.
So thank you Peter for the tip, and Philip for putting us in touch.