Treaty of Atlantia
The Antlantia Treaty's main effects were the ceding of Atlantia to the Assyrian Empire, and binding Emeria to the service of the Assyrians (They forgot about it literally after the Assyrian delegate put his name on it). The Treaty opened all of Emeria's resources to the Assyrians, whether it be scientific or military, and as thus, Emerian "Mercenaries" have been employed numerous times against the Czech Republic, when the Assyrians were actually able to recall the treaty.
But the blow that hit the Emerians hardest, was the unrestricted basing of Assyrian soldiers within Emerian borders, and with them, the despised religion of Trianglism. This inspired riots all over the Emerian Empire against the Assyrians and their Triangular temples, which resulted in severe punishments.
However, there were benefits, as with the stationing of Assyrian soldiers, the Peach abominations have been ruthlessly hunted down, now by two of the most anti-peach empires to-date.