Airdale War
| Airdale War | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| |||||||||
| Belligerents | |||||||||
 Sunrosia |
 Estmere | ||||||||
| Commanders and leaders | |||||||||
| |||||||||
| Strength | |||||||||
|
4,658,000 | |||||||||
| Casualties and losses | |||||||||
| |||||||||
The Airdale War, also known as the Estmerish-Sunrosian War, was a military conflict between the Sunrosian Monarchy and the Kingdom of Estmere. Lasting from 13 May 1918 to 23 November 1921, the conflict was primarily caused by Sunrosian claims to the Airdale region, lost to Estmere in the War of the Triple Alliance.
On 6 May 1918, the Sunrosian government of Rudolph von Waldriek issued an ultimatum to Estmere, requiring the cession of the three border counties of Ashdale, Bardonshire, and Gulval within 48 hours. A general mobilisation was ordered on the same day by Sunrosia, confidently expecting a negative answer. On 8 May 1918 at 4 PM, as the deadline ran out and the Estmerish government failed to answer positively to terms of the ultimatum, the Sunrosian Monarchy officially declared war on Estmere, with several Sunrosian units having already started hostilities an hour early.
The Strakonitz doctrine - the Sunrosian strategy - was to penetrate as deep into Estmere as possible beyond the contested Airdale in the initial assault, with the aims of forcing the Estmerish government into seeking peace, conceding the Airdale and paying war reparations that were necessary to the heavily indebted Sunrosia after the Great Collapse. Having prepared for that exact conflict, Sunrosian forces were able to occupy a fifth of Estmere including the major cities of Lumbridge and Morton within the first five months of the war. By November 1918, a series of successful Estmerish counter-offensives along the X and X rivers turned the tide of the advance and forced the Royal Sunrosian Army to retreat west; towards a line of fortified trenches. Hopes of a quick Sunrosian victory were ended as Strakonitz doctrine was left in ruins.
By January 1919, both sides had dug into a matching pair of trench lines in eastern Estmere and the war devolved into a war of attrition. While pre-war technological advances had allowed for the creation of stronger defensive systems, that development went unnoticed until then: offensives employing massed infantry advances and massive artillery bombardments suffered severe casualties as they ran into entrenchments, barbed wire, machine gun emplacements and return artillery fire. The front lines remained stable throughout 1919 and 1920 despite multiple bloody attempts at breaking the stalemate, most notably the Battle of X in September 1919 with a combined 700,000 casualties, and the Battle of X in April 1920 with over a million casualties.
In February 1920, the Estmerish launched the Roberts-Rushford Offensives, on the northern and southern part of the front respectively. The twin offensives were the first to feature large-scale use of landships, allowing for unprecented breakthroughs and were highly successful: Sunrosian forces were almost expelled from Estmere by June. With internal troubles rising and casualties accumulating, the Sunrosian military concluced on a final counter-offensive under Paulus von Kalwis, aiming to gain a favourable position to end the war on. Using of infiltration tactics, military aviation, panzers, and poison gas, the Sunrosian forces succeeded in regaining most of the territory lost in the previous offensives by October.
However, the Sunrosian victory would be short lived. Facing massive mutinies in the army, anti-conscription and anti-war protests throughout the entire country, and nearing economic collapse, Waldriek was forced to resign and his successor Kaspar von Stenhofen sought peace with Estmere. The Armistice of X was signed on 23 November 1921, although hostilities sporadically continued for two more days, and Sunrosian forces retreated to the pre-war border. The war officially came to an end two weeks later with the signing of the Treaty of Rimmington, essentially concluding the war with what amounted to a status quo ante bellum with neither side obtaining concessions from the other.