Before 1400

300 years before had been the Crusades, a claim to the holy land, all were victorius in the end, but lost after the crusade, but there was one thing which evolved from the crusades, a number of States, they controlled a pieace of land, they were Warrior Monks. There names were Crusader States, also called Tempelars and Hospitallers, these states were driven from the holy land to Europe whre they remained. The Tempalars gained land in Prussia, the Hospitallars were massacerd in France and Surrounding Countries.
In Asia Samurais were becoming powerful, they were (Espicillay Japans) Asias Knights! then From Central Asia came a new threat the Mongols, they came racing down from there steepes and into China. They conquered China and Korea, reached the Japanese Ocean and crossed it. They were killed, no, Masaacred when they landed. In Russia the Ruling State was Kiev, controlling a lot of land a even more land Paying Tribute to them. Trading ways were made by the vikings in the 9th centuries around Russia, they were used effectivly. But the Mongollians power reached even Europe and they even reached Hungary and the Ionain seas. Italy was divided into powerful City States which gained power from the Worlds first Bankers. Main ones were Florence,Venice,Milan,The Papal Staes,Naples. The Pope changed locations several times, going from The Papal States to France, several times there being 2 popes. The Swiss united in the Face of the Holy Roman Emprie, uniting the area around them. In England several revolts happened, one of the main ones being Wat Tylers. Scotland rebelled and gained independance under Robert The Bruce, in 1328 Ebgland finnaly recognised Scottish Independance. In 1337 the Hundred Years war started with great victories for the English at the Battle of Crecy and Poitiers. Plague was going around but the biggest being the Black Death,killing millions in Europe. And finnaly the Renaissance started in the age you have to rule!
Treatys
Military Accses-You can March through there land.
Defense Treaty-You re to defend the others country and they help defend yours.
Ceasefire-You stop fighting for a while.
Negotiating Treaty-To your terms
Protectarate-They are your vassal.
There are a few more.

Diploamcy
England At war with France
Venice,Florence,Milan and Naples at war with eachother.
Mongolia and China at war
Korea and Japan at war.
Scotland and England At war.
Spain and Portugal at war.
Morocco and Spain at war.
Scotland and France allied.
poland and Milan at war
Austria and Hungary at war.
Russia and Poland at war.
Khanate of AstraKhan and Khanate of Crimea at war with Ottoman Empire.