The Sutican War, also known as the Merryweather War or the Mustache War, was a large-scale conflict between the Holy Orenian Empire and the Begrudged Alliance, an international coalition spearheaded by the Free State of Sutica. The conflict's roots can be traced to the unresolved disputes stemming from the conclusion of the Rubern War: from its victory declared in 1760 after twenty years of stalemate, the Empire sought to affirm its status as the leading political force of the realm through subduing the lingering sentiments of resistance embodied within the new Sutican leadership. On the other hand, the Allied nations sought to check the Orenian advance, forgoing their disputes to deliver a fracturing blow to Orenian hegemony. What was meant to be a swift, punitive campaign soon turned into a global conflict marked by terror tactics and years of trench warfare. Though effectively a stalemate much alike its preceding conflict, the Empire saw its offensive halted in its tracks and its armies stretched to their limits, opting to concede defeat rather than risk further humiliation in a prolonged conflict. The conclusion saw both the Empire and the Allied forces commit to jointly ending the Inferi invasion of Korvassa instead, also marking a brief rise of Sutican prestige until the abdication of its victorious monarch three years later.
The ascension of Corwin von Alstreim, an outspoken Renatian loyalist, to the Sutican throne in 1762 saw the once-friendly relations between the Holy Orenian Empire and the Sutican State, already harmed by Josephite raids on Sutica and the State's subsequent entry into the War of the Two Emperors and intervention on the Renatian side, sour even further. Though many in the Empire favored a total absence of interaction between the two polities, certain factions within the Orenian leadership sought to both further the Empire's strategic goals in the south of Arcas and eliminate a potential threat which would arise through continued tolerance of a Pertinaxi loyalist monarch owing no fealty to Oren.
The opportunity for action presented itself in 1772, when a personal dispute between King Corwin and Master Peter Amadeus de Sarkozy resulted in the young nobleman's demise in combat. Throughout the following three Saint's Weeks, the Orenian diplomatic corps sensationalized the incident, presenting it to the Orenian public as a cold-blooded murder in a display of Pertinaxi barbarism. King Corwin's elimination of a newly-risen rogue faction within the Sutican State, which sought to overthrow Alstreim governance for the purpose of establishing a mage-led dictatorship in Sutica, further fueled the efforts of Imperial propaganda, which had by now convinced the public opinion of Helena that an armed intervention in Sutica was necessary so that its tyrannical regime might be removed from power. All the while, elements of the Imperial intelligence sought to gain favor among members of the Sutican Council with offers of protection under Orenian vassalage and a continued Orenian naval presence in the Sutican port, should King Corwin be delivered to face a show trial in Helena.
Though a complete avoidance of war seemed to be the formal course of Sutica in the first days of the diplomatic crisis, King Corwin and his closest advisors understood that an Orenian invasion seemed imminent and could only be defeated in battle, rather than averted entirely. A series of secret diplomatic meetings with nations aligned with Sutica, or sympathetic to the cause of opposing Orenian dominance, took place between 1773 and 1775. The Sutican Minister of Peace, Mika Goldhand-Uialben, exercised his diplomatic connections to ensure the realms of Urguan, Norland and Vanmark would support the cause of King Corwin, and view the Orenian incursion and violation of Sutican sovereignty as the latest incident in the sea of many similar transgressions committed upon these states in the service of Orenian expansion. These nations swiftly agreed on the principle that further Orenian aggression could only be checked by an all-encompassing defensive treaty. The alliance also found itself bolstered by a contract with the mercenary company of Hangmen, whose leader, unbeknownst to the allies at the time, boasted a claim to the Orenian throne as a Prince of Horen blood.
These agreements remained secret until a formal declaration of war was issued by the Orenian Empire in 1775. Its intelligence found itself stunned by the Sutican diplomatic offensive, as the defenders announced the formation of the Begrudged Alliance.
The war was massively unpopular in the Kingdom of Haense, whose people felt they were being dragged into a war that didn't pertain to them. The Lord Lieutenant Nicholas Barbanov declared Haense's support for the Empire in 1776, leading to the suicide of King Sigismund II. His seven year old son Josef then took on the throne. The war cemented the Haeseni populace against the Empire, who had endured a long string of grievances beforehand.
- 23rd of the Deep Cold, 1775 - Battle at Hangman's Keep - Allied Victory
- 8th of the Grand Harvest, 1778 - Battle of the Whispering Woods - Allied Victory
- Peter Amadeus de Sarkozy, an Imperial nobleman and nephew of Joseph Clement, Duke Helena, is killed in combat with the Trade King of Sutica, Corwin von Alstreim.
- The Imperial government delivers an ultimatum  to the Sutican Council, demanding the extradition of the Trade King to face trial for supposed murder.
- An attempted coup of Sutica is foiled by the Trade King, with the assistance of Cerulean Watch loyalists and Vanmark auxiliaries. Both sides begin preparations for war.
- On the 4th of the Grand Harvest, the Holy Orenian Empire declares war  on the Free State of Sutica. The Sutican Council issues a full rejection of the Orenian ultimatum  and intervention and mobilizes the Cerulean Watch.
- On the 10th of Sun's Smile, Sutica signs a contract  with the Hangmen of Hangman's Keep, a prolific mercenary company situated on the border of the Grand Kingdom of Urguan with Oren. The Hangmen corps, numbering over three thousand experienced soldiers, pledge their blades to the defense of Sutica.
- On the 8th of the Amber Cold, the Kingdom of Norland and the Princedom of Vanmark, along with Urguan, join the Sutican-led defensive coalition named the Begrudged Alliance. 
- On the 23rd of the Deep Cold, Trade King Corwin and Field Captain of the Hangmen, Prince Antonyus Horen, sanction an Allied incursion into Orenian territory. More than twenty high-profile Orenian citizens are seized by the Hangmen and brought to Hangman's Keep to be ransomed or executed. An Orenian regiment fails to liberate the prisoners, suffering a defeat at Hangman's Keep. Orenian raiders strike at the city of Sutica. Allied raiders strike at the Imperial city of Owynsburg. Both incursions are beaten back with minimal losses to the defenders.
- Allied correspondence with the King of Hanseti-Ruska, Sigismund II, is intercepted by Imperial agents. The Imperial liaison in Haense, Lord Lieutenant Nicholas Barbanov, preemptively mobilizes the Haeseni forces in support of Oren, preventing Haeseni non-involvement in the war. King Sigismund II commits suicide and is succeeded by his seven-year-old son, Josef, placed under regency. The regency affirms Haeseni support for the conflict, much to the dismay of Haeseni citizens. Widespread demonstrations against Imperial rule commence.
- The Imperial State Army begins its offensive. The combined forces of the Begrudged Alliance, under joint command and bolstered by Renatian loyalists of the old Pertinaxi regime, set up entrenched positions along the road to Sutica. The conflict devolves to trench warfare, much alike the Renatian advance in the Atlas Coalition War some ninety years earlier.
- The year is marked by frequent frontline skirmishes, in which the Allied forces frequently gain the upper hand. A shortage of war material is reported in Helena.
- Allied leadership issues two declarations: The Reformation of House Horen  and The Blood-Raven's Rebuke , detailing post-war goals.
- On the 8th of the Grand Harvest, the Imperial State Army launches a full-scale assault on Allied positions in the Whispering Woods. The offensive is beaten back, reinforcing the stalemate and Orenian failure to achieve a breakthrough, despite minimal losses.
- The Church of the Canon, having previously backed the Orenian invasion, negotiates the Palatine Concordat , an armistice between Oren and Sutica under pain of excommunication, plagued by concerns of the advancing Inferi forces in the Korvassa. Peace negotiations commence between the warring parties.
- On the 4th of Snow's Maiden, more than five years after the Orenian declaration of war, Sutica and Oren sign the Peace of Merryweather , effectively ending the conflict. The Empire withdraws its charges and condemnation of the Trade King, its forces departing the frontline. Sutican sovereignty is recognized by the Empire.
- Peace treaties are signed by Oren and the remaining warring parties, effectively dissolving the Begrudged Alliance.