The music was written by violinist Georges Boulanger with lyrics by Carlos Gomez Barrera in 1926 as Avant de mourir (Before dying). I don’t think it was recorded. The English lyrics were added by Jimmy Kennedy in 1939.
Glenn Miller took it to No 2. I really don’t think this is very good.
The Ink Spots reached No 3 the same year with a far superior version.
It has been recorded many times – Wikipedia lists 64 versions.
Roy Orbison tested his voice to the limit and a bit beyond on his 1963 album In Dreams.
P J Proby gave it the full treatment as the B-side of his 1965 single That Means a Lot.
I will spare you Ray Conniff, Bert Kaempfert and Mantovani.
And so to the best version, by the Platters in 1956, with the brilliant lead vocalist Tony Williams. It made No 1 in America.