The hall was packed with people who, by the looks of them, weren't born in 1967, back when Scott Walker was as big a star as Robbie Williams. In their eyes Scott Walker is a misunderstood genius, an indie pioneer, a prophet without honour, a man who apparently had to wait until today to get his due. This narrative is repeated by Luke Walker in a review in The Guardian.
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It's not quite the way I remember it. Scott Walker was a very big deal in the Walker Brothers but he was still a very big deal as a solo artist. His albums were in the shop window. He was played on the radio. He had his own TV series. And it wasn't stuck away in late night. It was prime time BBC television.
As for "the albums struggling commercially", the first three were all top-three hits and the fourth might have done the same if he hadn't made it more difficult for himself by putting it out under his birth name Scott Engel. Then he made a few albums of covers just to run down his contract. As for his name fading he had a big hit with "No Regrets" when he rejoined the Walker Brothers in 1976.
Scott Walker was never actually forgotten. He was simply adopted by another generation and they preferred to think they were the ones who discovered him.