Domenico Modugno

He was, without a doubt, the progenitor of singer-songwriter music. His songs (which on the whole remain immense), unfortunately aged poorly and in the '70s he never managed to evolve. Then in the '80s, after the stroke, he was forced to say a final goodbye. Also charming as an actor and TV entertainer. I would lean towards a 4 but I give a 5 for historical significance.