Alright... Thanks guys... You gave me some good leads for web searching that I hadn't thought of.
Here's what I found so far about the turn of the 16th century...
England - Henry VII rules England. The first of the Tudors, he gained the throne by killing the last of the Yorkist Plantegents in battle. He had trouble with a couple of 'pretenders' who tried to take the throne from him. He stregthened the monarchy, but stayed rather aloof to both the populace and nobility. An excellent politician, he made England rich by bringing the country out of feudalism and into 'modern' trade and law.
France - Louis XII was king. Generally regarded as a just and moderate king to the French, he waged war against Spain for the various Italian provinces and occupied several of them, including Genoa, Naples and Milan (though he could not hold Naples against Spain).
Spain (Aragon & Castille) - The marriage of Ferdinand II & Isabella I united all of Spain, except for Grenada, which they conquered in 1492. Best known for patronizing the voyages of Christopher Columbus, they also expelled the Jews and Moors from Spain and instituted the Inquisition. They divided the New World with Portugal in the Treaty of Tordesillas. they fought against France in the Italian Wars, and gained control of Naples, Sicily and Sardinia. Isabella died in 1504.
Portugal - Manuel I ruled during the 'Golden Age' of Portugese history, during which the Portugese explored the New World. His court was a haven for arts, sciences and law. Vasco de Gama discovered the route around the Cape of Good Hope to India. Expeditions to Brazil and the Americas. Commercial relations opened with Persia, China and Japan were opened. He also sponsored a great many missionary enterprises, and expelled the Jews from Portugal in 1497 & 98.
Scandinavia - Hans King of Denmark, Norway and Sweden had a rather unremarkable reign distinguished only by the successful rebellion and seccession of Sweden.
Poland & Lithuania - King Alexander and later King Sigismund II suffered from both internal struggles with Russian and Moldavian Rebels, but also external wars with the Teutonic Knights, the Muscovites and the Crimeans. They were notoriously poor kings, which made them, to a certain degree, subservient to the Polish senate and nobles.
Germany - Maximilian I was King of Germany and Holy Roman Emperor, but was never actually crowned by a pope and so can never really be considered more than an Emperor-Elect. He obtained the Netherlands and Burgundy through marriage to Mary, daughter of Charles the Bold. The fought against France in the Italian Wars, joingin the Holy League. He reformed the constitution of the Holy Roman Empire. Later, he arranged marriages to bring the monarchies of Hungary and Bohemia under Hapsburg control.
Ottoman Empire - Beyazid II "the Just" was the sultan of the Ottoman Empire was a patron of both western and eastern culture, and worked hard to ensure smooth-running domestic politics. He engaged in minor conflicts with Venice, but rebellions in the east of the empire and clashes with Perisa were a greater concern.
The Papal States - Alexander IV (Rodrigo Borgia) was corrupt and immoral, but gained little real power as pope. He had many misteresses who bore him several bastard children whom he openly acknowledged, including the Cesare (who employed da Vinci) and Lucretia. Pope Pius III (Francesco Todeschini Piccolomini) was made pope in September 1503 and arrested Cesare Borgia. He filled the office for less than a month before he died (on Oct. 18) of an ulcer in the leg. Pope Julius II (Giuliano della Rovere) became pope with the political support of Borgia, after which he devised a series of plots to it decidedly uncomfortable for Borgia to remain within the Papal States. He then set about consolidating central Italy, and moved against Venice with the help of France, Germany and Spain via the League of Cambrai. Later, he had to make peace with the conquered Venetians to expel the foreign armies. Afterwards, he organized the Holy League of Ferdinand II, Henry VIII, Emperor Maximillian, and Venice to drive France back across the Alps. Aside from his political and military abmitions, he was also the friend and patron of Bramante, Raphael and Michelangelo.