On July 14th, 2011, a large group of North Lander mercenaries and others affiliated persons and groups attacked Forward Base Ojala, a military base located close to the Barboneian border within the North Lands, directly north of the Barboneian city of Etuvartiokaupunki, also within the North Lands. While attacks on Barboneian towns and other Barboneian properties within the North Lands by the natives were common, this attack showed signs of being much better coordinated and aggressive, as if it were attempting to uproot the Barboneian military forces in the area and force them out. While North Landers were commonly known to use more primitive weaponry such as spears, bows, and occasionally muskets or other such weapons, this attack saw the usage of artillery and more modern weaponry, perhaps seized from dead Barboneian-affiliated mercenaries or purchased from arms traffickers operating in the region.
Damage done to the base was minor and few casualties were sustained. However, this was the final straw for the Barboneian Commonwealth Military's high command. Attacks had been occurring in the area ever since the military base had been erected in the 1980s, and attacks on transportation convoys and oil refineries were increasingly common, especially in the 2000s. With the attack on the base and other unrelated attacks being used as justification, the Minister of Defense, Gabriel Vanhatalo, was able to secure a declaration of war from the Barboneian parliament, the Kansanedustus, on the North Lands as a whole. Any non-Barboneian entities in the North Lands were declared hostile.
On July 16th, the newly christened Operation Northern Retaliation began, a joint military strike between the Barboneian Army and Air Force. The Air Force, led by Kenraali (general) Henrik Toivonen, paved the way for the invading ground forces by utterly annihilating any marked "hostile" hamlets or villages, destroying over two dozen in a massive perimeter around the border, leading to massive yet so-called "acceptable" civilian losses from native North Landers, many of whom having absolutely nothing to do with the attacks. Following this, the Greater Barboneian Army moved into the North Lands, led by General Victor Ardenstotz. Over 200,000 soldiers were mobilized, with half having been reserves called into active duty.
The Barboneian military, with superior firepower and mobility, were able to quickly and easily mop up remaining mercenary and insurgent forces in the established perimeter, and set about securing the perimeter directly in an attempt to stem any more North Lands forces from being able to enter the area. For the first time in nearly a century, the border area finally seemed to be at peace, at least, for the Barboneians. North Lander natives residing in the area were greatly mistreated by the occupying forces, and due to "an increasingly hostile environment", humanitarian groups such as the Barboneian branch of the Red Cross had difficulty reaching many areas that needed aid the most. Reports of Barboneian troops terrorizing and brutalizing the natives were incredibly common and reached much of the Barboneian homeland and the rest of Valkia despite a media blackout that had been ordered by the Barboneian government.
The actual "Northern War" really only lasted for less than a month, for major attacks by the North Lands insurgents and mercenaries effectively ended by August 2011.
For the rest of 2011, COIN operations continued throughout the established perimeter. Despite the initial successes in destroying the mercenaries and insurgents, the Barboneian military had difficult permanently putting down any groups that were in the area due to their constant movement, leading to even more retaliatory attacks on villages thought to be holding insurgency groups. The native populace was becoming increasingly hostile to the occupying troops, and morale had decreased drastically following the "Massacre at the River Valkoinen" in November, when a large group of Barboneian soldiers were ambushed and killed by North Landers while they were resting along the Valkoinen River. Shocking images of the seemingly superior Barboneian troops having been slaughtered brutally did much to decrease popular support back in Barboneia.
Additionally, outside of the perimeter, surveillance became increasingly difficult, where much of the area had been unmapped and locals who knew the areas refused to cooperate, leading to troops sent further into the North Lands interior going in completely blind. Combat effectiveness was dropping rapidly, and less soldiers were being sent out to counter the insurgent attacks.
In February 2012, a mass of attacks along the perimeter border stations led to the perimeter being decreased by 10%, and then 25% by 2014. The number of troops stationed in the area was also lowered drastically, from approximately 150,000 in 2012 to just 90,000 in 2014. The area beyond the perimeter has been essentially declared lawless and savage, and no more troops were ordered to pursue enemies into it.
By 2019, the operation officially continues in the North Lands, but has been reduced to a modicum of its former self. Attacks still occur on oil refineries and military outposts throughout the perimeter, and an overall threat still lingers over the region. A skeleton force of barely over 20,000 active soldiers remains within in the perimeter, supplemented by private military contractors such as the Extra Territorial Group. Thankfully, humanitarian aid has increasingly been allowed to enter the region in the last few years, but many natives still remain hostile to the occupying forces. Attempts to gain support by the local populations have almost always ended in failure. Back in Barboneia, the continued military occupation of the area has been highly contested in the parliament, with no agreement on the issue in sight. Being deployed to the area is extremely dreaded by many Barboneian active soldiers.
At this point in time, nearly a decade after the initial invasion and occupation, the operation seems to have no end in sight, and will likely continue for quite some time.
Approximately 4,523 Barboneian soldiers have been killed in action in the North Lands. 14,292 have been wounded, and over 2,000 were reported missing in action. Over 20,000 native North Landers, non-affiliated with the insurgency or mercenary groups, have been reported killed, and many more wounded.