The First Battle of Plainville is one of many battles prior Sachstein Invasion of Brune of Madan no Ou to Vanadis, where a Brune defending force, lead by Scheie and Earl Bouroullec, suffered a disastrous defeat from the hand of Hans von Klugel, the commander of south branch Sachstein invasion force at Plainville Hills, near Nemetacum. Hans’ battle fort tactic not only proven to be useful against Brune’s signature Calvary charge formation, it also caused great trouble to Tigre and his companies in later battles.
The Kingdom of Sachstein had long tried to invade Brune through the western border. However, their numerous attempts were stopped and repelled by Roland and his Navarre Knights. During the Brune Civil War, Thenardier had signed a peace treaty with Sachstein so he could deal with Silver Meteor Army and Ganelon without facing pressure from the west. However, with Roland murdered, Faron passed away, and Thenardier killed in battle, there was no one left to defend Brune's western front, King Augusto decided it's the right time to invade again. He called two of three his most trusted generals - Leonhardt and Hans, for Leonhardt to lead an expedition force of 50,000, straightly head for Nice from Brune's western front; while Hans lead an army of 20,000 from southwest, putting pressure on Nice.
The nobles around Nemetacum who were supporters of Thenardier did not put up any resistance against Hans' army. They, under the command of Melisande Thenardier, even assisted Hans' army by providing supplies and guidance in hope to overthrown Regin's rule, so Hans' army passed Nemetacum with an ease. They then camped at the hills of Plainville, built up a battle for, and waited for any news from Leonhardt. Meanwhile, Shael, commander of Lutece Knights Squadron, along with Earl Bouroullec, received order and gathered a force of 10,000 to repel Hans' force, it didn't take too long for two forces to face each other.
With Brune Army's took a toll of nearly half of the army's casualties, only 7,000 survivors (including Scheie and Bouroullec) narrowly survived Sachstein Army's relentless onslaught and they were forced to retreat from Plainville Hills. Of all 7,000 survivors however, merely 5,000 men in Brune Army were remain active. Brune Army's second disastrous defeat not only further crippling Brune's morale, it also further solidified the Sachstein Southern Invasion unit's impenetrable Hill Fort where it was used as their headquarters to observe Brune Army's next move. Eventually, the newest disaster would spread across kingdoms within the continent, prompting Tigre and his new army, including another Vanadis Valentina, marched for Brune as the Brune Army's newest reinforcements. It would take Brune Army at least three rounds or even utilizing Valentina's scheme to finally breakthrough Hans's Army's tactics and eventually scattering Sachstein's (Southern Unit) advance.