A chronological list of all of Euno's Crusades:
The First Crusade: Starting approximately 155 years ago, Euno began to impose its reign on the rest of Altsia. They established a treaty with one of the neighboring kingdoms, Mydar, and invaded their second neighbor, Caplus. They continued to take other kingdoms, until an alliance of Kira, Thesni, Hurin, and Regza pushed them back into their new borders, ending the First Crusade.
The Second Crusade: 83 years ago, once again using Mydar as an ally, Euno made their strongest push, using Keyblade wielders as shock troops for the first time. This new tactic allowed them to push aside Thesni, Hurin, and Regza, pushing right to the door of Kira's capital city, only to overextend in their haste and have their supply lines fall apart from guerrilla strikes. Kira rallied, pushing them back and establishing the current borders.
The Third Crusade: 24 years ago, Euno finally turned on its long time ally, Mydar. In a single night that marked the beginning of the Third Crusade, General Sigmund Rage and a contingent of trained keyblade wielders wiped the nation off the map. This time, however, Kira was prepared. They rallied their armies and pushed against the Eunoian advance, maintaining the present borders. The war lasted for 14 bloody years, with neither side gaining much ground. In a final push, Euno managed to drive the center of the Kiran lines back to the Verdant Plains, only to be pinched between the northern and southern lines. Euno was again rebuffed, and suffered enough losses to end the crusade.