Throughout the history of art a number of themes have persisted, with religion being one of the most persistent. And within that category, there are quite a number of additional persistent images. Naturally the most common are Jesus himself, followed by Mary. Because these two are so central to religious art, there has not been much in terms of variation in the way they've been depicted that cannot be accounted for by the simple evolution of painting styles. However the third most common subject matter in religious art seems to have offered artists over the centuries a great deal of latitude both visually and thematically. And in terms of their sheer numbers in religious art, they are by far the most common figures depicted. While their popularity (and that of religious art in general) has waned somewhat during the last century or two, there now seems to be a renewed interest amongst the public in general, if not necessarily amongst artists. If you haven't guessed by now, I'm talking about the multitude of angels that have populated the panels, walls, and canvases of artist for almost a thousand years.
Some of the earliest, existent, painted depictions of angels date back to the early thirteenth century. They are figures from a fresco Last Judgement painted by Pablo de Casserres. Ambrogio Giotto painted some surprisingly realistic angels in his 1305 fresco, Lamentation. Fra Angelico gave them human proportions a century later in his The Annunciation. At the same time, other artists used them as hardly more than decorations and they began to assume whimsical, childlike qualities. However about the time of the Renaissance there seems to have developed a split in the way angels were depicted. There were the putti (cute, chubby little toddlers with wings) and the "serious" angels, the archangels, Gabriel, Michael, Raphael, Metraton, Uriel, and Satanel. Each of these, partially from the Bible, and partially from secular writings, developed their own persona, tradition, and visual amenities. And in addition to these, there was the ubiquitous "Angel of Death" known as Azrael.
Today, we most commonly link the painting of angels with the work of Raphael, Botticelli, Leonardo, and a host of other Renaissance, Mannerist, and Baroque masters. But lest you think the visual tradition kind of stagnated with Rubens, El Greco, and Grünewald, you might be surprised to find that Rembrandt painted angels, so did the Rococo artists, as well as Goya, Blake, Rossetti, Gauguin, and Chagall to name just a few more recent painters to employ such heavenly beings in their work. Perhaps the most interesting thing regarding angels and art is not who painted them but how they have been painted, and how they have changed over the years. Unlike Christ and Mary, angels have offered exciting creative opportunities and a wide range of activities in which artist have legitimately exploited them. And with renewed popular interest in angels today, a few artists have once more begun using them, usually in a decorative mode. Also television and movies have taken up the calling, and whether they come sans wings a la Michael Landon, or with John Travolta's heavy overcoat, their images continue to evolve to fit their earthly missions.