So in writing up the background the Skandaharian language tree has kinda exploded in dialects and detail. This is what I have written so far, just concerning one branch:
The Skandaharians are the equivalent of the Proto-Germans. The Great Rain of Fire decimated the population of the Skandaharians due to their proximity to ancient Blackmoor. Most of the tribes had become subject to the superior civilization of Blackmoor and were destroyed along with it. The few who survived were more primitive hill tribes who occupied the southern hills of modern Heldann. Three major tribes, the Goths, the Antalians, and the Vanitar, formed out of the surviving Skandaharians and expanded into the northern territories as the long winter caused by the GRoF began to subside.
The Known World of Dracopolis: The Low Goths
by Lance DuncanAs the various Skandaharian tribes scattered among the frozen territories of the north, the Goths remained behind and settled the lowlands of the modern Heldann region. Over time some of the Goth tribes migrated to the fertile mountain valleys of the north, but a portion always remained in Heldann. The different Gothic groups began to separate and evolve over time and those in the lowlands became known as the Low Goths(equivalent to the Ingvaeonic Germans.) while those in the high mountain valleys became known as the Old Goths. The Low Goths had some contact with the Dunharians on the Isle of Dawn and the remnants of the Thonian tribes to the south and their culture began to be influenced by them over time. They came to call their land Gotland and themselves Gotlanders.
Over the course of the centuries empires rose in the south, first the Nithians, and then the Thang. Each of these in succession made attempts at incorporating Gotland into their domains but ultimately proved unsuccessful; the wild hills of Gotland proved to be too harsh for the armies of the south. Truth be told, the greatest threat to Gotland was the Mengul goblinoids from the mountains to the west; the goblinoids repeatedly conducted raids on the lowlands, pillaging and destroying homes and fields. A cycle of destruction and rebuilding became the norm among the Gotlanders.
This all changed in BC 160 when a massive horde of Goblinoids came pouring out of the mountains. Many Gotlanders were killed, but many others fled, some north and some south. Those who went north fled to the elves of the Rhien Forest who offered humanitarian aid. With the combined efforts of the elves and the Gotlanders the Goblinoid horde was defeated in a great battle in the Skaufskogr hills. The Goblinoids took possession of all the lands between the Gotland and Skaufskogr hills, while the Gotlanders spread into the lands north of the Skaufskogr hills and Rhien Forest. These Low Goths assimilated the few Antalian tribes living in this southern coastal region and called their new land Nordurland. This remnant of the Gotlanders have become known as the Nordur(the equivalent of the Old Saxons) after the name of the land the land they come from.
The majority of the Gotlanders who fled from the invading goblins turned to the rich lands of the south. The great Gotlander horde defeated the armies of the Gwynish Kingdom led by King Atruaghin, who was slain in battle. The native Gwynish who were not enslaved or killed by the Gotlanders fled into the mountains of Rockhome. The Gotlander horde dispersed as it settled this new land, some settled the eastern isles and some settled the coastal fjords and plains. The isles became known as Ostland and their inhabitants the Ostish(equivalent to the Old Frisians), while the mainland became known as Vestland and the inhabitants the Vestish(equivalent to the Old English). Shortly after the fall of the Thang Empire, missionaries came to the land of Vestland, and the King converted to the the faith of the one true Church. Through his influence many Vestlanders came to see the light and The Church grew in power and influence throughout the kingdom.
This period of peace was not to last however. Lured by the wealth of the unprotected monasteries of the Church of Vestland, raiders from the northern regions of Norwold began plundering the rich land of Vestland. After a century and a half of constant raiding many of the raiders stopped simply raiding and began to settle in the lands of Vestland and Ostland. This was followed by the invasion of a great heathen army led by King Cnute the Bold who conquered the Kingdom of Ostland. After Cnute's death, his sons invaded Vestland. As a consequence of these invasions the Vestish and Ostish have been for the most part assimilated or oppressed by their northern overlords, and many have returned to the old ways and worship the old gods in imitation of their overlords, though a few maintain faith in the one true Church despite the persecution they receive for their beliefs.
A single Vestland kingdom has been able to withstand the armies of the north time and again, this is the Kingdom of Ghyr(equivalent to Wessex). Ghyr maintains the true faith and the kings of Ghyr hold out hope of reuniting Vestland under a faithful Vestish King. Just 30 years ago the King of Ghyr entered into an alliance with the King of Ylaruam to the south, and with his aid was able to defeat many of the northern jarls and expand the domain of Ghyr.
So for the language tree that would look like -
Skandaharian(proto-german)
---> Low Gothic(Ingvaeonic)
---------------------------------> Gotlander
------------------------------------------------> Nordur(Old Saxon)
------------------------------------------------> Vestish(Old English)
------------------------------------------------> Ostish(Old Frisian)