It was Pope Gregory in the late sixth century who fortuitously declared: "Painting can do for the illiterate what writing does for those who can read." The endorsement spurred generations of churchmen to support some of history's greatest artists through commissions for devotional paintings and church frescoes.

Barons and feudal lords, however, were also early patrons of the arts, fuelled by the desire to glorify their battleground triumphs for posterity. The Bayeux Tapestry, which depicts the Norman Conquests, is one of the few surviving examples.

Michelangelo was one of many subsequent beneficiaries of patronage. He received numerous commissions from the wealthy Medicis of Florence. And, of course, by Pope Sixtus IV (after whom the Vatican's Sistine Chapel was named) whose nephew, Pope Julius II, commissioned the young artist to produce ceiling frescoes.

Royal patronage had taken over from church by the 17th century when kings and princes throughout Europe latched on to art as the ultimate status of power. Louis XIV was, perhaps, the best know champion of French design and commissioned numerous paintings to commemorate state occasions.

Charles I, meanwhile, gave a welcome boost to Van Dijk who was talent- spotted by the English art connoisseur the Earl of Arundel. After a sabbatical touring Italy, Van Dijk took up residence in a studio in Blackfriars with the honorary position of "principale painter" to Charles I and Queen Henrietta Maria.

The 20th century saw the rise of private patrons eager to invest their millions in new art and be seen to champion the innovative and avant-garde. Major collections of modern art have been nurtured by the likes of Getty and Sainsbury, and, of course, by millionaire ad man Lord Saatchi.

Meanwhile, art has truly moved mass-market in the Nineties with the spread of artists in residence in prisons, hospitals and even accountancy and law firms like Mischcon de Reya, which recently put a poet on the payroll. Pope Gregory, it seems, had a point. MC