The Northerners were a massive ethnic group of ponies originally native to the Far North, a vast swath of land that was notably colder than the rest of Equestria, was the cradle of ponykind, and was also the region where the events of the Hearth's Warming Eve Pageant took place.
Originally all of ponykind were Northerners, living in the colder regions of Equestria. When the land began to turn against them and become colder, some sought out new homes for themselves and discovered the land that would one day be known as the nation of Equestria. When the nation was founded by the union of the three pony races and tales of the land's bounty reached back up north, many ponies still remained in the old homelands, too emotionally and culturally attached to leave for the greener plains of Equestria.
After the Windigos were cast away from their land, the Far North became more hospitable. After the unicorns' duty with controlling the cycle of the day and night passed to Princess Celestia and Princess Luna, there came a time of intense magical research. During this era, many a unique school of magic were founded. The practitioners of one particular new form of magic were called Mancers, ponies or other creatures that had an affinity with a particular element. Several classes of Mancers were discovered, but cryomancy was the one school forbade and shunned by the Northerner culture due to the great animosity they had toward snow and ice. Mancers became far more uncommon after Nightmare Moon's advent and the war that would eventually follow.
Aproximately twenty years before Nightmare Moon returned, The Far North began to freeze over and became much colder due to global environmental change. The Northerners were forced to pack what little they could carry and flee from their homeland with minimal preparation. This journey later becoming known as The Great Exodus and would be known as the worst disaster in Equestrian history up until the balefire apocalypse, claiming twenty-million lives with eight-million missing. Equestria accepted the Northerner refugees, and the nations of Equestria, Zebrica, and Aldorna rendered aid as a state of emergency was declared. The Equestrian cities of Burrlin, Manehattan, Stalliongrad, and Moscovo were notable for accepting large numbers of refugees. Manehattan in particular grew much larger, an entire district sprung up becoming known as the Northern quarter.
The Northern ponies intergrated well with their Equestrian neighbours, the strain their arrival put on the economy eventually balancing out after twenty years. The Northerner ponies held a three day festival in several cities to embrace their own culture and remember the millions who died or were lost during the Exodus, an event known as the Northern Lights Festival.
The Northeners were a proud and diverse people, equally as advanced as neighbouring nations. They had numerous subcultures within their ethnic group and made innovations in magic and architecture which were almost lost during the Exodus.
Thulians, Horweigans, Haysians and Hokkadans were all cultures that were part of the greater Northerner pony heritage and were the few to survive The Great Exodus. Their cuisine, history, and cities were all annihilated by the the fierce snow and ice that now engulfed the Far North. Hokkaidans were notable for having a warrior culture that included the philosophy of Bushido and also a lifestyle also known as The Way, which helped guide Hokkaidans in living their lives.
The Mancers were a unique school of mages that originated in the Far North. Certain equines (not just limited to unicorns or even ponies) could only specialize in a specific branch of magic should they be born with an elemental affinity. Mancers were such people able to command the elements including their subcategories. For example, hydromancy was the primary school of water magic with cryomancy and atmidomancy being branches within that tree. The Mancers existed primarily in the Far North. Mancer magic could also be practised by non-unicorn races, given the proper time, training, and elemental affinity.
Learning a particular school of this branch of magic has its costs however. Learning this school of magic can and normally will result in physiological and psychological changes in their practitioners as the Mancer furthered his or her elemental union.
Pyromancers - Their body heat rose and they became more susceptible to lower temperatures, requiring them to move to hotter regions to live comfortably.
Hydromancers - Their bodies were known to grow gills and webbing that would allow them to live underwater but found it much harder to live on land due to rapid dehydration.
Cryomancers - Cryomancers cannot stand to be around hot flames or other heat sources and make performing their brand of magic more difficult. They are much more resistant to the cold, perfectly happy in artic climates. They also seem to have an instinctual fear of fire.
Terramancers - They developed a need to stay on the ground and were reluctant to part with the earth- even going up a set of stairs could be a challenge for them. Some Terramancers feared leaving the ground so much that they lived in caves or underground.
Anemomancers - They specialised in magic and had an obsession with flight and staying off the ground. This would often result in the death of its non-pegasi/griffin practitioners
Electromancers - Their bodies required they ingest some form of electricity or magical energy in order to survive
Umbramancers - They required living in shadows and darkness and found living in the light uncomfortable.
Spectramancers - Needed to be around light and were very uncomfortable when not under some form of light.
The Northern ponies were known for cooking a wide range of foods exotic to the Equestrians- most notably ramen- but cabbage, rice and seaweed dishes were also known as part of the Northern cultural cuisine range.
Northerners, like their southern counterparts, have a wide range of coat colors and recieve picturesque cutie marks on their flanks when they discover their special talent or purpose in life. Their most notable feature are their eyes and muzzles, which are respectively slanted and sharper much like those of a zebra.
Northerners are herbivores like other ponies. Due to living for generations in the Far North, they have developed an above-average, natural resistance to cold weather and cold temperatures.