The Brothers' War, also referred to as the Orenian War for Succession or the Novellen Civil War, was a major civil war between the two successors to the Holy Orenian Empire, Prince Peter Augustus and his younger brother Prince Frederick Charles following the loss of the War of Wigs and sudden death of Emperor Philip III and his wife, Empress Anastasia I. The two brothers disagreed on the future path of the Orenian Realm and thus called all Orenian vassals and peers in 72 S.A. to support their claim.
In the days following the Empire’s surrender in the War of the Wigs, Emperor Philip III passed away from his wounds in battle. Subsequently, Empress Anastasia I died of grief in the County of Mardon. Following the Empress's death, Prince Frederick marched upon New Providence, taking the city and proclaiming himself Frederick I, King of Oren and dissolving the Holy Orenian Empire. Having received word of an oncoming attack shortly before Frederick’s arrival, Prince Peter fled Providence to the nearby lands of the Duchy of Reutov. There, he began rallying support for his cause alongside his principal supporters: his uncles, the Duke of Reutov, Ivan Ruthern, and Prince John Casimir.
Skirmishes, Battles, and Sieges
- 5th of the First Seed, 72 S.A. - The Battle of Vuillermoz - Royalist Victory
- 12th of the First Seed, 72 S.A. - The Standoff at Fort Linnord - Stalemate
- 5th of the Sun's Smile, 72 S.A. - Battle of Reutov - Royalist Victory
- 14th of the Sun's Smile, 72 S.A. - Battle for New Providence - Royalist Victory
- 72 S.A.
- Shortly after signing the Peace of Eastfleet, Philip III passes away.
- Anastasia I, overcome with grief from the death of her husband, dies alongside him in the County of Mardon. This is witnessed by three of her children: Victoria Augusta, Anna Ulyssa, and Frederick Charles himself.
- Upon hearing of the death of Philip and Anastasia, the men of Blackvale and Arichsdorf, led by Margrave Willem, Margravine Laurentina, and Prince Hadrian, seize control of Providence, opening it to Frederick.
- Following his mother's death, Frederick Charles rallies the Bannermen of Mardon and marches to the Imperial Capital of New Providence. He is met with open gates and his forces quickly occupy the city. After breaching the gates of Aster Hall, Frederick ascended to the dais, where he announced the dissolution of the Holy Orenian Empire and proclaimed himself King of Oren.
- With the dissolution of the Empire, the lands were divided into the Kingdom of Oren and the Grandmarch of Westfall, held by Laurentina and Willem.
- Having heard of Frederick’s cause, Prince Peter Augustus flees to the nearby Duchy of Reutov.
- Several imperial vassals swear fealty to Frederick I in the first days of his rule, including the County of Aldersberg, Viscounty of Rivia, Barony of St. Lothar, Barony of Artois, Barony of Pompourelia, Viscount of Valles and the County of Provins.
- Westwards in the Grenz region of the Empire, a faction sponsored by the Duchy of Reutov proclaim Philip III's and Anastasia I's eldest son, Peter Augustus, as Holy Orenian Emperor. He is met with support from the Duchy of Azor, Duchy of Sunholdt, County of Huntshill, Viscounty of Vuillermoz and the Barony of Darkwood.
- Despite initially swearing fealty to Frederick Charles during his court session in Providence,members of the Barony of Pompourelia declare support for the Imperialist faction. Several other houses begin to fracture in loyalties, including the Viscounty of Rivia, Viscount of Valles, County of Provins, Baron of de Rosius and the Barony of Darkwood.
- Overcome with stress due to the war, the Barony of Brighthill declares neutrality.
- Royalist forces intercept Imperialist forces at Vuillermoz. A battle ensues and leaves the Royalist forces victorious, capturing Peterist leader the Duke of Reutov. He is then executed by his bastard Andrezj Barrow in the Aster Hall.
- Following the Battle of Vuillermoz, the County of Halstaig and Barony of Ames declare support for Frederick Charles.
- The Principatus of Ebonwood, one of the largest Orenian vassals, declares neutrality in a missive entitled, Proclamation of Extremus. 
- In response to the growing concern of limited manpower, Sir Erik Othaman founds a secondary Imperialist Army known as the "Foreign Legion," its purpose is to allow untrained volunteers to funnel into the Imperialist armed forces.
- Peter IV marries Lucia d’Azor, daughter of the Duke of Azor in a ceremony held in Vuillermoz. During the wedding a dragon flies overhead, boosting the morale of all Imperialist supporters as a proclaimed sign of God’s blessing.
- House Ivanovich under its new patriarch the Baron Andrezj Ivanovich declares support for King Frederick of Oren by public decree. 
- The Hounds of Don declare their allegiance to Peter IV, and join the war on the Imperial side. 
- After being captured by Royalist forces, Joseph d'Azor swears neutrality on behalf of the Duchy of Azor.
- The House of Alstion pledges its fealty to Peter IV, and thus the Principality of Alstion enters the war.
- The Duchy of Reutov constructs a new city that shares the same name, and it becomes the capital for the Imperialist cause.
- Following the completion of Reutov city, Royalist forces storm the city and spark the Battle of Reutov. The Royalists manage to capture Emperor Peter IV and bring him to Providence
- To avenge the Battle of Reutov and rescue the Emperor, Prince John Novellen personally assembles as large an army as he can muster and attempts to storm New Providence, sparking the Battle for New Providence
- The Battle for New Providence ends in a Royalist victory, with Emperor Peter IV being slain by Andrezj Petyr Ivanovich following the battle and the Imperialist forces being utterly annihilated.