In the first century BC, Roman villas at seaside pleasure centers like Stabiae, on the Bay of Naples, not far from Pompeii, were filled with frescoes, furniture, and the like, though deeper research reveals that art collecting wasn’t just the demesne of the elite. Reproductions of Greek paintings abounded, as artists had access to the originals in Naples and Rome. The story of widespread collection might reasonably be traced to a moment of widespread production: the Renaissance. Cosimo de’ Medici, the first of the Florentine political dynasty that would usher in the flowering of Italian art, was a patron of both Fra Angelico and Donatello and established a familial and state commitment to the arts that reigned for centuries.

One of the most noteworthy instances of middle-class collectors sprang up in the Dutch Golden Age, during the 17th century. Scores of well-to-do merchants were hungry for art, and their drive to collect and display pieces of art in their homes played a large part in the flowering of Dutch painting. In a telling turn, the subject matter of Dutch masters like Rembrandt, Brueghel, and Vermeer tended away from classical or Biblical scenes and toward contemporary portraiture and city scenes, individuals over icons.

Throughout much of Europe, collecting was still done by the aristocracy, and the centuries after the Renaissance were dominated by royal collections. Art for the masses saw a dramatic rise in the 17th and 18th centuries, as the elite moved their prodigious piles of art from drawing rooms to public museums. The Medici’s Uffizi gallery revealed its treasures to the public in 1765, and Catherine the Great’s Hermitage followed suit in 1852. The creation of other royal museums, like the Louvre and the Prado, marked a huge step forward, if not in the widespread ownership of art, at least in terms of public access to it.

Perhaps the greatest dissemination of a major body of work—–and the death knell for royal collections—–came after the French Revolution, when all of the royal Orleans family’s art was sold off to the newly flush urban elite of industrially revolutionized London. British industrialists were suddenly visiting auction houses—–the first, Christie’s, held its first auction shortly before the French Revolution—–and serious collectors and dealers gradually shifted their attention from the halls of royal power to the salons of the bourgeoisie.

The era of great American collection didn’t kick into high gear until the Gilded Age (the later third of the 19th century), when an emerging coterie of fabulously wealthy, well-traveled businessmen and women took advantage of hard financial times in England and elsewhere in Europe to quickly assemble vast collections that might otherwise have taken generations.

In the last two decades of his life, J. P. Morgan bought over $60 million worth of art (that’s more than $1.3 billion in today’s terms), and other patrons like the Vanderbilts, Henry Clay Frick, and Isabella Stewart Gardner joined the firmament of U.S. super collectors. Unlike their European counterparts, though, Americans often had strong philanthropic bents, with huge collections given to or used to found museums.

The American public also showed a surging interest, if not actual participation, in collecting at the turn of the 20th century, helped along by massive exhibitions like the 1893 World’s Columbian Exposition in Chicago. Much like the Romans two millennia before, the U.S. middle class engaged in a brisk trade in reproductions, this time for the wildly popular Orientalist style favored by the Salon painters of France.

By the middle of the 20th century, a booming middle class, more museums and galleries than ever, and an uptick in the number of art fairs brought more and more Americans into contact with the art market.

Today, the notion of what is even collectible—outsider art, posters, videos—–is as broad as it’s ever been. And the modes of buying art are equally vast: specialty dealers, traveling shows, the Internet. Serious collecting is still a well-moneyed pastime, but as the avenues to acquiring art continue to widen, collecting grows just that much more democratic.