Helian War

Helian War
Part of Pan-Septentrion War
Date 2 April 1937 - 24 June 1946 Location Helian Ocean Result Entente victory End of the Pan-Septentrion War Fall of the Dayashinese Empire Formation of the Republic of Dayashina Weakening of Casaterran colonial powers in the Helian Ocean Menghean Civil War Hanhae War Sundanese Revolution Independence of many East Meridian states Ceding of the Divine Island Chain to Dayashina Rise of Tír Glas as a world power Glaso-Tyrannian occupation of Dayashina Removal of all Dayashinese troops from the Helian Ocean Temporary disbanding of the Imperial Dayashinese Armed Forces Seizure of Sakurajima by the Septentrion League
Belligerents
Entente Tír Glas New Tyran Viceroyalty of Vinya Viceroyalty of Sundan Tyrannian Far-East Territories Sylva Sylvan Far-East Territories	Hemithean Axis Dayashinese Empire Hanhae
Commanders and leaders
TBD	Shogo Genki Suzuki  † Gen Yutaka Ueda Gen Kantaro Yamaguchi  † Adm Yasuhiro Oniishi  †
Strength
5,000,000	4,750,000
Casualties and losses
750,000+ dead	650,000-750,000 dead

The Helian War was the largest theatre of the Pan-Septentrion War, spanning across nearly the entirety of the Helian Ocean, from Dayashina to Vinya. After a long buildup in the Dayashinese Empire, hostilities officially began with the Dayashinese reclamation of Ryujima from Tyran in 1937, and the subsequent repatriation of the Divine Island Chain from Tyran and Sylva. Hostilities began with Tír Glas in 1943 with the Battle of Inishmore. The war ended with the usage of the second and third atomic devices on Dayashina by Tyran in 1946, and with the ritual suicide of Genki Suzuki and his faction.

Tensions between Dayashina and Casaterra

In the years leading up to the conflict, tensions had been quickly rising between the Dayashinese Empire and various Casaterran powers. As Dayashina modernised and built up a powerhouse military-industrial complex, an increasing amount of people began to share the belief that Dayashina itself should ascend to a rightful dominant position in the East by doing away with the presence of the Casaterran powers, who they believed to be historical oppressors, purposefully holding down the might of Dayashina with all their power. Almost immediately, attention was drawn towards their presence in the Divine Island Chain, historical territory of Dayashina that had seen a vast increase in Casaterran presence in the midst of the Dayashinese Civil War, which gave rise to the Dayashinese Empire.

Citing the historical presence of Tyran and Sylva in Dayashina, the overwhelmingly negative and humiliating economic effects that came with it, and their clear opposition to the rise of the Empire, a new faction in Dayashinese politics, dubbed the Ascendancy Party, began to gain traction in the Imperial Diet with constant inflammatory rhetoric being thrown at neighbouring Casaterran holdings. The Ascendancy Party also commonly forwarded racist ideals, stating that the Dayashinese people were the master race and that some Casaterrans were "subhuman product of the devil." The Party believed that the Casaterran Empires such as Tyran and Sylva represented not only the greatest existential threat to Dayashinese culture, but also the most virulent and potent evil that the world had ever seen. Furthermore, they continuously pushed for the prioritisation of the strengthening of the Dayashinese military-industrial complex, aligning with their view that the neighbouring evil could only be dealt with through absolute force.

The Ascendancy Party, while they struggled in their early years, eventually were able to not only sway popular support in their direction, but also gain the approval of a number of extremely important Imperial military figures. They finally took the seat of governmental power in 1900, and immediately began instituting policies to align with their stated values. The military became the center of society in Dayashina, secondary education began pushing racist ideals, and various elements of Dayashinese culture were actively manipulated to fit the needs of the Empire. The military began sending students off the Casaterran states to not only study the basics of modern military doctrine, but also to find weaknesses in such a doctrine and develop independent strategies to defeat them. The Imperial Dayashinese Navy was progressively built up into one of the most powerful navies in the world. The withdrawal of Dayashina from the Septentrion Naval Treaty instilled an increased feeling of worry in Tyrannian, Sylvan, and Glasic diplomats.

All of the international worries culminated to truth in 1935, with the election of Genki Suzuki as the Dayashinese head of government. By then, the Ascendancy Party had all but complete control of the Imperial Diet, and Suzuki represented the most extreme of the Party's views. Suzuki formed a cadre of elite Imperial military personnel, called High Command (abbreviated as HighCom), which placed the now built-up military under his wing. HighCom was unified by a desire to reclaim the Divine Island Chain (later, HighCom would split into two factions for various reasons).

On 28 March 1937, Genki Suzuki ordered the immediate removal of all Tyrannian presence from Ryujima and Sora, and all Sylvan presence from Aijuku and Shogazu. Tyrannian and Sylvan diplomats lobbied to hold a diplomatic meeting with Suzuki, but were stonewalled on more than six occasions. The Imperial Dayashinese Navy moved into position around Ryujima and Sora, while Suzuki continuously made demands for the Tyrannians to leave. After no reconciliation, Suzuki declared war on the Tyrannian Empire and Sylvan Empire on 2 April, 1937.

Dayashinese offensives, 1937-1939

Divine Island Campaign

This campaign began on 2 April, 1937, immediately following the issuing of a declaration of war from Dayashina to Tyran and Sylva. The Imperial Dayashinese Navy unleashed a week long bombardment of the Tyrannian garrisons on Ryujima and Sora, reportedly resulting in over a thousand casualties on each occasion, forcing the Tyrannian soldiers into makeshift fortifications and tunnels.

Dayashinese aircraft low-level bombed Tyrannian vessels and encampments in and around the Maya River

On the 7th of April, IDN Marines made landfall on Ryujima, facing limited resistance on the beaches. IDN Marines were able to breach a deep hole in the middle of the Tyrannian frontlines, subsequently branching out to the sides and systematically destroying resistance alongside the small detachment of armour embedded with the force. Resistance was reportedly weak and disorganised in general, as the Tyrannian forces had suffered heavy losses in the initial bombardment, and were forced to move out of advantageous fortifications and into less optimal areas of cover. Dayashinese troops also reportedly came across scores of Tyrannian troops suffering from untreated jungle-induced diseases, as the medics focused nearly all of their attention on the injured from the catastrophic initial naval bombardment. All in all, 5,203 Tyrannian troops perished on the island, in comparison to the 1,136 Dayashinese dead over the course of a week of fighting. About 1,000 Tyrannian troops surrendered when the IDN Marines reached Tyrannian governmental estate on the island. With specific orders from General Yutaka Ueda, the Dayashinese troops on the island treated the POWs relatively humanely, supplying food and medical supplies to them before instituting them for minor labour within the Empire. The Tyrannian diplomat on the island, however, was executed due to Genki Suzuki's incessant behest. Similar events occured on Sora, with the fighting ending quicker, the island having a smaller garrison than Ryujima. 2,350 Tyrannian soldiers and 632 Dayashinese soldiers perished on Sora, with a further 600 prisoners of war being taken.

Following the rapid victories accrued on Ryujima and Sora, the Imperial Dayashinese Navy moved into position around the Sylvan holdings of Aijuku and Shogazu. After about two days of continuous bombardment on both of the islands, the Sylvan diplomats agreed to surrender, saving the lives about 7,242 of their troops after a further 1,821 had perished in the bombardments. IDN Marines landed on the islands to claim the prisoners, who were distributed amongst the Divine Island Chain to rebuild airfields and naval yards for the Imperial Dayashinese Navy and Imperial Dayashinese Air Force. Because of their early surrender, the Sylvan diplomats were allowed free passage back to Maracaibo.

This campaign, being a sweeping victory for Imperial Dayashina, resulted in a monumental growth in confidence in the military by a number of members in the High Command, including Suzuki. These members vied to push Imperial Dayashina out of its shell and to further continue their conquest onto neighbouring Casaterran territories. The other faction of High Command, including the legendary General Yutaka Ueda and Admiral Yasuhiro Oniishi, argued that their counterparts were trying to achieve a very long term goal too quickly, stating that their rapid hastiness would cost Dayashina in some form sometimes down the line. Ueda argued that a defensive war against two declining empires, as Menghe rose, could be won easily, but that biting off more than they could chew would come with a risk far too great for Dayashina to handle. Suzuki countered this argument by stating that Tyran and Sylva had already issued their declarations of war against Dayashina, and so there was no point in waiting for them to come back to the Dayashinese home islands, when the creation of an ocean-spanning buffer would make such a prospect extensively harder. Eventually, Suzuki's side of the debate won majority amongst High Command members, and Imperial Dayashina turned its attention to the Tyrannian protectorate of Sundan.

Battle of Sundan

The Imperial Dayashinese Navy turned its attention to Sundan in 1938, following the Battle of Portcullia wherein a Dayashinese carrier force embedded with the Imperial Menghean Navy to inflict severe losses on the Tyrannian fleet there. With Tyrannian vessels attempting to retreat to Sundan for repairs and regrouping, the Imperial Dayashinese Navy began to hunt the retreating ships, making heavy use of submarines and carrier-based aircraft strikes to sink a number of Tyrannian ships and force them to retreat deeper into the Helian Ocean, leaving Sundanese waters and Tyrannian trade coming from Sundan completely unprotected. The IDN waged submarine warfare on Tyrannian merchant vessels, sinking dozens of ships carrying tonnes of goods before they could reach their destination.

Dayashinese and Tyrannian diplomats met in Penang preceding the battle. Takuro Mutaguchi, front and center on the Dayashinese side, is seen reacting angrily toward the resolve of the Tyrannian diplomats

Eventually, the Imperial Dayashinese Navy appeared in force on the coast of Sundan. The Empire sent diplomats into the capital, where the Tyrannian seat of government was based. On the first day of discussions, the Dayashinese diplomats explained to the Tyrannians, in grueling detail, the situation that they were currently in, in hopes that they would surrender the sizeable garrison of about 50,000 Royal Army soldiers and 120,000 local soldiers through this mode of psychological warfare. It quickly became apparent that the Tyrannian diplomats would not budge through a threat. On the second day, the Dayashinese diplomats came with proposals for a conditional surrender of Tyrannian troops on the island, guaranteeing their humane treatment within a Dayashinese-held Sundan, citing the treatment of Tyrannian POWs on Ryujima as evidence that Dayashina would adhere to the agreement. Once again, the Tyrannian diplomats denied any notion of a surrender. Bewildered, the Dayashinese diplomats returned to the ships. After a three day long grace period in between discussions, the Dayashinese diplomats returned with an even more favourable proposal, guaranteeing everything entailed in the second day's proposal, as well as free passage of Tyrannian officers back to Tyran. The Tyrannian diplomats, for a third time, denied the proposal, arguing that Sundan was extremely critical for Tyrannian operations in the east and could not fall at any cost. This time, one Dayashinese diplomat, Takuro Mutaguchi, reacted with anger, stating that the Tyrannian diplomats and their men would be killed for their impudence. In private, Mutaguchi noted in his diary that he had gained a certain amount of respect for the Tyrannians in their conduct, it being not so dissimilar from the Dayashinese in nature.

After diplomatic talks collapsed, the Imperial Dayashinese Navy and Air Force began a limited bombing campaign on critical parts of the Sundanese capital island. Dayashinese fighter aircraft were able to out-manouevre and defeat Tyrannian air groups. After the initial aerial battle, which lasted about 64 hours, the Dayashinese aircraft began to target government estates with strafing and bombing runs. It was reported that six out of the eight Tyrannian diplomats which refused surrender were killed in the limited bombings of St George (Penang), the capital of the Tyrannian protectorate of Sundan. Simultaneously, Dayashinese ships and other aircraft besieged large Tyrannian encampments, forcing the Tyrannian troops to hunker down and providing cover as the IDN Marines landed on Penang. Tooth-and-nail urban combat ensued in Penang as Dayashinese troops made slow progress through the city, fighting against Royal Army troops and locally contracted soldiers alike. It was reported that Dayashinese armour struggled in combating Tyrannian armour present in the capital, and so the Dayashinese armour were relegated to back-line fire some compositions were changed to be geared towards an anti-armour role. What resulted was an increase in pace of the Dayashinese offensive, as Tyrannian armour found themselves generally overwhelmed by the wide scale employment of anti-tank rifles, towed guns, and anti-tank grenades by the Dayashinese infantry. Furthermore, the Dayashinese troops were ordered to temporarily retreat from sectors pact heavily with Tyrannian armour and anti-armour material, allowing for the IDN to unleash a hellish bombardment on multiple sectors of Penang, resulting in the destruction of many Tyrannian armoured assets.

Dayashinese troops advancing through the streets of Penang in close quarters combat

With Tyrannian armoured capability significantly weakened, Dayashinese infantry were able to push further into the city at a more rapid pace. While both the Dayashinese Marines and Army personnel and the Royal Army personnel were both inexperienced, the Dayashinese infantry were able to gain an edge with veterans of the Divine Island Campaign reporting widespread successes in their engagements, spearheading the offensive in Penang. Tyrannian officers stated that a lack of communication with local army units, inexperienced officers, and lack of coordination between army groups led to a very disorganised defence in Penang, with the Dayashinese able to come away with decisive victories in large engagements. After about three weeks of fighting, the Dayashinese infantry were able to reach half-leveled diplomatic district of Penang, and took hold of the two remaining Tyrannian diplomats, who were found hiding in a large underground bunker below the capital building. General Yutaka Ueda encouraged the Tyrannian diplomats to issue an order for the immediate surrender of Tyrannian forces on Penang and Sundan as a whole. The two diplomats denied the encouragement. After a further week of fighting, Ueda demanded a ceasefire on behalf of all Dayashinese forces, and extended a personal invite to the commanding officer of Tyrannian forces in Penang to discuss a surrender. The officer, by the name of Johnson, agreed to the invitation, and met with Ueda on an Imperial Dayashinese Navy ship, where they reached an agreement for the conditional surrender of all Tyrannian forces on Penang and Sundan. The agreement entailed, once again, humane treatment of Tyrannian POWs in the territory. Additionally, the agreement included the contraction of the local army groups as a branch of the Imperial Armed Forces, to serve as enforcers of Dayashinese policy on the island. The agreement stripped the legitimacy of the Tyrannian seat of governance on the island and transferred it to the Dayashinese government in Nakazara, with the diplomat Mutaguchi being entrusted as the new governor of the territory. After discussions, General Johnson was flown to Dayashina by the IDAF, being the first Tyrannian officer held in the "District of Esteemed Foreigners", where he lived out the rest of the war in relative comfort.

All in all, about 7,000 Dayashinese troops had perished with a further 10,000 wounded, while 11,000 Tyrannian troops perished with a further 12,000 wounded. Local army groups reported heavy casualty rates, with about 15,000 casualties reported in central Penang alone. About 130,000 personnel in total, including over 40,000 Royal Army personnel and over 90,000 local embeds, surrendered to Imperial Dayashina. The majority of Royal Army personnel were contracted in labour of varying degrees of difficulty around Sundan, as the islands were repurposed for the Dayashinese war effort. The local army groups were reformed and instated as a subordinate institution of the Imperial Armed Froces, serving as police and enforcers under the command of Dayashinese government and overseeing personnel. The prisoners of war from Sundan would receive some of the best treatment of the war, until the return of Tyran to the islands in 1945.

Continuation of Dayashinese offensives, 1940-1942

Battle of Dickenson Islands

With the solidification of Axis grip on the South Menghe Sea and the Treaty of Maracaibo (1939) guaranteeing a steady and safe supply of petrol, the Dayashinese Empire turned their sights on the Helian Ocean. The Tyrannian Helian fleet was in rapid retreat, trailed closely by the Imperial Dayashinese Navy. Dayashinese naval aviation harassed the Royal Navy fleet all the way to Dickenson, where the Royal Navy fleet then unsuccessfully attempted to hold for repairs and to transport Royal Marines off of the islands. A brief engagement ensued as IDN and RN vessels traded blows, with the overwhelming firepower of the IDN being too much for the dwindled RN fleet to handle. Dayashinese naval aviation proved extremely effective over the islands, denying dozens of troops transports passage to their mother ships, inflicting nearly one thousand casualties until the Royal Navy completely withdrew from the islands.

Though the Royal Navy managed to transport approximately 6,000 men off of the islands, there were a further 35,000 trapped on the islands to face the IDN Marines. With Dickenson Islands serving as the home base of the Royal Navy's fleet in the Helian, it was extremely heavily fortified, with modernised and optimised facets of cover for the Royal Marines. The IDN launched a massive bombardment of the island for three days, but nearly all of the Tyrannian soldiers ended up surviving due to their pre-built underground fortifications. 80,000 IDN Marines with accompanying personnel landed on the islands to face down the well-prepared Royal Marines.

On the beaches, Dayashinese personnel encountered a wave of fire almost instantly, with Tyrannian soldiers popping up in semi-destroyed coastal fortifications to unload on the IDN Marines with small arms and artillery fire. The mainline force of the IDN Marines found themselves trapped on the beach until nightfall, being forced to hunker down while they moved tank barricades and awaited for a penetrating blow to be dealt. That blow came around midnight, when the Dayashinese naval aviation had finally taken out the majority of the Tyrannian ground-based anti air power, which made it impossible for Dayashinese planes to support their infantry without taking significant damage for about 12 hours. Dayashinese planes relentlessly bombarded Tyrannian artillery encampments for two hours, from 22:00 to 00:00, until inclement weather made it impossible for the planes to operate optimally or safely. With the fire rate of Tyrannian artillery significantly slowed, the cover of night and heavy rainfall, and with a fair amount of tank blockades removed, General Junichiro Nakafumi ordered the IDN Marines to press up.

IDN Marines advanced uphill towards Tyrannian fortifications with minimal cover. A heavy barrage from Dayashinese machine guns meant for counter-suppression worked marginally to keep the Royal Marine machine gunners from having free will to operate, but casualties on the advance were still high. To the surprise of the Dayashinese, the majority of the Royal Marines held their positions staunchly, even when confronted up close by an overwhelming number of opponents. The IDN Marines utilised flamethrowers, grenades, armour, and light artillery to dispatch the Royal Marines from heavily entrenched positions. In the surrounding area and back line of the coastal defences, close quarters combat ensued, with several melee engagements being reported from both ends. An unrelenting Dayashinese advance came crashing onto an unmoving Tyrannian defence, leading to brutal, bitter fighting for the next three hours. By the time the sun was rising, the majority of the Tyrannian defenders had either been killed or had retreated. A total of 17 prisoners were taken by the Dayashinese attackers. The IDN Marines recorded 1,524 casualties on that night alone, with the Royal Marines recording 2,140. That engagement would become famed as "The Bitter Morning" in the lore of both the Tyrannian and Dayashinese military.

With the coastal defences completely overwhelmed, the IDN Marines began a piecemeal and slow advance deeper inland. Tyrannian defences dotted at every meter of the islands slowed the advance of the Dayashinese significantly, with the IDN Marines having to knock out a fortification to gain a few meters of ground, just to be forced to repeat the process, slowly becoming more fatigued as tiredness or casualties ramped up. However, the 17th Infantry Regiment of the Dayashinese Marines managed to make significant breakthroughs, taking hold of the Hampton Dockyards and several heavily fortified positions within a week's worth of fighting. Tyrannian General Gage Thompson attempted launched a counteroffensive to retake the dockyards, which caught the 17th Infantry Regiment off guard. Several hundred Tyrannians sprinted and bypassed a massive number of Dayashinese infantry, breaking through a weak point in their lines and nearly breaking through to the dockyards, but they were stalled by the 3rd Tank Regiment, sustaining heavy casualties as the Dayashinese armour laid heavily into their attack. The attackers were then flanked by the men of the 17th Infantry Regiment that they had bypassed. Out of the 800 attackers, 640 were killed, and 160 were taken prisoner. The gamble, which nearly worked, proved crippling in the long run, as Dayashinese infantry across the islands re-focused the majority of their efforts to the sector which now had far less resistance, which allowed the IDN Marines to reach the Dickenson Islands Air Base in force in a matter of less than 72 hours following the attack.

-Air Base attack-

-Final holdouts-

-Cleanup and surrender-

-Stats-