Bindo Altoviti (1491-1556, painted by Raphael about 1515)
Fabio notwithstanding, gorgeous blonde guys are few and far between in Western male portraits. But this picture of Bindo Altoviti, a wealthy young Florentine who was a prominent Renaissance banker (!) and art patron, certainly makes a case for fair-haired gentlemen. In fact, the story behind this portrait is so shamelessly romantic, that I'm quoting at length from the National Gallery of Art's web page:
[In the portrait, Bindo]"turns in a dramatic, almost theatrical, way to fix the eye of the viewer. Perhaps one viewer in particular was meant to receive his captivating look: Bindo's wife Fiammetta Soderini. Renaissance poets and courtiers were unanimous in believing that a person first fell in love through the eyes. They were called the guides of love, which could reveal the passion within more effectively than the tongue itself, or letter, or messengers. Bindo's flushed cheeks contribute to the impression of passion, and a ring is prominent on the hand he holds above his heart. The robe slipping from his shoulder reveals a bare nape caressed by soft curls. Their golden color would have underscored the nobility and purity of his love.
"Bindo and Fiammetta, daughter of a prominent Florentine family, were married in 1511, when Bindo would have been about twenty. The couple had six children, but Fiammetta continued to live in Florence while Bindo's business with the papal court required his presence in Rome. This portrait, which apparently hung in the couple's home in Florence, would have provided Fiammetta with a vivid reminder of her absent husband."