Since their was no native population, European colonies had less to deal with as far a revolts went. But since none knew the land, massive starvation was common in the Americas until several discoveries by Sir George McKinley.
Vinland was one of the first European colonies, starting around the end of the XI Century. It had far less difficulties than what it had on OTL as there were no revoltous natives. However, cold forced them to stay within the shore boundaries, and only small settlements were built until the late XIV Century. After the Scandinavian's conversion to Christianity, the VInlanders remained with an important minority of Scandinavian pagans.
Cristoforo Colombo and the Caravel
The Caravel was invented within the late 1430's in the Republic of Pisa, in their last important cause. 14 years before Lorenzo de' Medici, the Pisans only had 10 years of independence left and didn't do much to use it. Piero de'Medici conquered Pisa in 1440 and started exploration attempts. However, it was not until Lorenzo de' Medici got power in 1466 and with the Granadan Secession of Gibraltar that the Italians could use it for a truly effective manner. Led by explorer Cristoforo Colombo, they discovered a new land (OTL La Guajira) and named all of OTL Colombia "Lorenzia", in the name of Lorenzo de' Medici. This is how the first European colony was founded.
The Italian colony was destinated to slow but sure success. Expanding through the shores and eliminating much of the Lorenzian forest, the Italian created a large empire stretching through the north of South America and Central America.