His likeness, thanks to Holbein's famous portraits in the Thyssen-Bornemisza Museum and elsewhere, is so well known that it almost qualifies as a brand.
Gregarious, engaging and comfortable in seven languages, David cultivated relationships with the likes of dealer Kahnweiler and billionaire art collector Baron Hans Heinrich Thyssen-Bornemisza, who bought works by Picasso, Kandinsky and Italian futurist Giacomo Balla.
Unlike more ambitious collectors such as Baron Thyssen-Bornemisza, whose broad range of master-paintings is housed at the imposing Villahermosa Palace in Madrid, Mr Beyeler does not claim to have mounted an exhaustive panorama that takes in every movement in 20th-century art.