Unorganised

Huscarls
Champions, bodyguards, and retainers of jarls and chieftains, Huscarls are the elite warriors of any ruling lord or clan leader. A minor lord may employ only a handful of men, whereas jarls and kings may command a hundred men or more. Expensive to maintain with the finest weapons and armour, their training alone make each member highly valued and, in many cases, irreplacable. In battle, Huscarls will stay by their lord's side come-what-may, acting as the last line of defence or the vanguard depending on said lord's level of involvement.
Berserkir Lodges
Utterly fearless in battle, Berserkirs throw themselves into the fray with reckless abandon. Typically lightly armoured that they may overwhelm their foes with superior speed and freedom of movement, they are sometimes stereotyped as mouth-frothing barbarians unable to tell friend from foe. They are known to partake in mysticism before a battle, inhaling strange incense and ingesting poisonous mushrooms to dull pain and numb their minds to fear. They charge the enemy with a bellow of laughter and song in their heart, fully devoted to the belief that the first to die is guaranteed a place at the All-Father's side. Berserkir Lodges can be found around the continent, often out in the woods where their sometimes disturbing rituals won't affect anyone, each Lodge carrying on their own traditions.
Organised

The royal bodyguard of House Heavenshield, these dozen men are chosen and trained by the High King himself in the arts of war as well as various Force techniques, requiring that they are Force-sensitive in order to join. As part of achieving full membership, they are to complete their training off-world at a Jedi temple of their choice that they might expand their minds and interact with the wider galaxy. Not merely great warriors, Lionguards are also inspiring leaders, disciplined generals, and even spymasters if the situation calls for subterfuge — each member a hero in their own right, they are taught to think and take whatever action necessary to perform their duty, their authority subservient only to the Lion King. They are headquartered in the capital of Heavenheim, though they come and go as their duties dictate.
Elite cavalrymen, these master horsemen drawn from across the Realm are famous for their imposing uniform, donning skull-faced helmets whilst adorned with two great wings arching from their backs, their appearance is as audacious as it is ostentatious. Rising to fame after the Great War, this band of brothers take after the mythical guardians of Heavenheim — the mighty gryphon; wielding great lances, the heavy cavalry unit swoops in and smashes into the enemy lines like a tidal wave, the sound of their hooves like rolling thunder. Their regimental headquarters resides in Heavenheim, with members swearing oaths of fealty to the city rather than the Crown.
Dawnguard
The sole Jedi presence on Midvinter, the order was established by Coci Heavenshield once she and her husband retired from galactic affairs, and serves as Grandmaster to this day. The Fortress of Dawn sits atop the Blessed Peak, tallest mountain in the west, and acts as a temple structure as well as a stronghold of the region. From there, the Dawnguard stay informed on galactic matters whilst keeping a wary eye on potential off-world threats using advanced technology foreign to the uninformed natives who consider them an enclave of magical healers and wise men capable of witchcraft. Though the disappearance of their Grandmaster in recent years has left them without a clear leader, they dutifully maintain their eternal vigil.
Gatesmen
The Gatesmen are the staunch defenders tasked with manning the many forts found along main roads as well as the gatehouses safeguarding travelers through perilous mountainpasses, and will sometimes act as escorts or guides. The greatest of such forts are called Westgate Pass and Trinity Cross, each a veritable fortress constructed to guard the crossroads between the Four Marks whilst limiting access into the lands of the Beorni. They draw recruits from all corners of the world, employing an army of blacksmiths and fletchers to provide them with arms and arrows.