The "Early Renaissance" was all about Florence. Firenze, as it's known to those who live there, was the place in which to launch one's artistic career in 15th-century Italy.
In the previous article on the Proto-Renaissance, several Republics and Duchies in northern Italy were mentioned as artist-friendly. These places were quite serious in competing with one another for the most glorious civic adornment, among other things, which kept a lot of artists happily employed. How, then, did Florence manage to grab center stage? It all had to do with five competitions. Only one of these was specifically about art, but they were all important to art.
Competition #1: Dueling Popes
In most of 15th-century (and 14th-century, and all the way back to the 4th-century) Europe, the Roman Catholic Church had the final say on everything. Keeping this in mind, it was of major importance that the end of the 14th-century saw rival Popes. During what is called the "Great Schism of the West", there was a French Pope in Avignon and an Italian Pope in Rome. Each had different political allies.
Having two Popes was intolerable; to a pious Believer, it was akin to being a helpless passenger in a speeding, driverless automobile. A conference was called to resolve matters, but its outcome, in 1409, saw a third Pope installed. This situation endured for some years, until one Pope was settled on in 1417. As a bonus, the new Pope got to re-establish the Papacy in the Papal States (read: Italy). This meant that all of the (considerable) funding/tithing to the Church was once again flowing into one coffer, and, say! The Papal bankers were in Florence.
Competition #2: Florence vs. the Pushy Neighbors
Florence already had a long and prosperous history by the 15th century. It had made fortunes in the wool and banking trades. During the 14th century, however, the Black Death wiped out half of the population and two banks succumbed to bankruptcy...which led to civil unrest and occasional famine, coupled with episodic, new outbreaks of plague.
These calamities certainly shook Florence, and its economy was a bit wobbly for a while. First Milan, then Naples and then Milan (again), tried to "annex" Florence, which was a juicy prize indeed. The Florentines were not about to be dominated by others, though. With no alternative, they repulsed both Milan and Naples' unwelcome advances. As a result, Florence became even more powerful than it had been pre-Plague, and went on to secure Pisa as its port (a geographical item Florence had not previously enjoyed).
Competition #3: Humanist? Or pious Believer?
Humanists had the revolutionary notion that humans, purportedly created in the image of the Judeo-Christian God, had been given the ability for rational thought to some meaningful end. The idea that people could choose autonomy hadn't been expressed in many, many centuries, and posed a bit of a challenge to blind faith in the Church.
The 15th-century saw an unprecedented rise in humanist thought because the humanists began writing prolifically. More importantly, they also had the means (printed documents - new technology!) to distribute their words to an ever-widening audience.
Florence had already established itself as a haven for philosophers and other men of the "arts", so it naturally continued to attract the great thinkers of the day. Florence became a city in which scholars and artists freely exchanged ideas, and art became more vibrant for it.
Competition #4: Let us entertain you!
Oh, those clever Medici! They'd begun the family fortune as wool merchants, but soon realized the real money was in banking. With deft skill and ambition, they became bankers to most of present-day Europe, amassed staggering wealth, and were known as the pre-eminent family of Florence.
One thing marred their success, though: Florence was a Republic. The Medici could not be its kings, or even its governors - not officially, that is. While this may have presented an insurmountable obstacle to some, the Medici were not ones for hand-wringing and indecisiveness.
During the 15th-century, the Medici spent astronomical sums of money on architects and artists, who built and decorated Florence to the total delight of all who lived there. The sky was the limit! Florence even got the first public library since Antiquity. Florentines were beside themselves with love for their benefactors, the Medici. And the Medici? They got to run the show that was Florence. Unofficially, of course.
Perhaps their patronage was self-serving, but the reality is that the Medici almost singlehandedly underwrote the Early Renaissance. Because they were Florentines, and that was where they spent their money, artists flocked to Florence.
The artistic competition? Think "Doors"