Well to the north of the Moonshaes and west of Faerûn are the home islands of the Northlanders, which exist as they have for centuries. The greatest of these islands, Ruathym, holds the oldest settlements the Northlanders claim, and from there, all manner of northern kingdoms and legends have sprung.
The Northlander Isles are scoured by strong winds and powerful waves, and also suffer biting, bone-chilling cold for most of the year. In deepest winter, the inlets are choked with ice, and fog lingers late into the day, if it breaks at all. Most wear furs to keep out the cold, and those going to war supplement their protection with thicker hides, and helms lined with wool or fur. They disdain magic and glorify battle, to the point that most communities grow restless when they don't have an enemy to fight.
Because the Northlanders are good at fighting and sailing, and perfectly willing to attack ships close to their shores, best to be cautious around any Northlander Isles, especially if you haven't been assured of safe passage, and often even then.
Northlanders pay homage to several deities, but they most honor Valkur, a hero-god of their own who exemplifies the qualities their warriors hold most dear. Take care not to question or insult this veneration in their presence.
While Northlanders revere many other gods—Auril, Umberlee, Talos, and Tempus, in particular—they see mighty Valkur as the most important. This hero-god is unique to the Northlanders and embodies the qualities that Northlanders most admire: fierceness, cunning, courage, strength, and sailing skill.
The fisherfolk and merchants of Gundarlun are more like their mainland cousins than most island folk. Unlike other Northlanders, they are less apt to start a fight with folk they don't recognize. Because of their more peaceful bent, you're more likely to be able to safely get fresh water and supplies in Gundarlun, though you should be prepared to trade generously during your stop.
More than a dozen settlements pay homage to the king in Gundbarg. They profit from the island's reputation as a safe stopover. Though Gundarlun might not provide the best seaworthy warriors, nevertheless ship s that are looking to make repairs, take on sailors or sail-menders, or store large cargoes are likely to find their needs met here.
If you seek shelter during a storm, you might find it in the many islands of the Purple Rocks. It was once my great fortune to find safe harbor at the port village known as Ulf of Thuger. The welcome I received was nearly as warm as I might have found among the Gunds, and I found the Rocklanders to be a fine audience for my tales of travel and adventure. However, something makes me think I shouldn't return.
On the day that the storm broke, I emerged from the longhouse in which I had been hosted and beheld a well-tended and organized settlement with green pastures and full fishing nets. The ship's crew and I were dealt with cordially by everyone, and the ship was already repaired and prepared for our leaving, the Rocklanders having apparently worked through the night to make it ready.
We left on good terms, and it wasn't until we were well away that we realized we all shared a strange apprehension. We had not seen much of women while we were on the island, which was to be expected since Northlanders typically house guests well away from the homes, farms, and forges that are the Northlander women's domain. But we also neither saw nor heard any children or young men, and never once did we see any old men or women. Indeed, I hesitate to say that any man among the Northlanders we met had a single gray hair on his head or in his beard. This strange fact, and the Rocklanders' weird custom of giving any human figure in their art the arms of their totem—a many-tentacled squid—makes me leery of a return.
The island of Ruathym is the ancestral homeland of all the Northlanders who live on the islands of the Sea of Swords and the humans who would go on to found old Illusk, now Luskan, and spread out as the Illuskan people. The warlike folk of Ruathym know they have this legacy, and they consider rule over other Northlanders and the cities of the coast to be their birthright.
Merchants can occasionally trade with Rauthym at its capital city, also called Ruathym, but I don't risk such a stopover if I can help it. One never knows when Ruathym is going to be at war, and any ship within sight of the island when it is will be fair prey.
Well to the west of its nearest neighbor, the remote island of Tuern is host to violent folk who raid and pillage at will and seek to enslave any outlanders they capture on or near their island. They trust no magic of any kind, and offer tribute to the red dragons and giants that dwell in the high mountain caves of this place. They have five kings, with a High King supposedly enthroned in their capital of Uttersea, but like any sailor with sense, I've avoided the island by a great distance, so I can't tell you which bloodthirsty knave currently rules the roost.
The tiny outcrops that make up the Whalebones are so numerous it's impossible to accurately chart them all. Each has its own legends and its own (often self-proclaimed) king, and they battle one another incessantly in skirmishes where the casualties number in the dozens, at most.
The Whalebones are so called because of the scattered skeletons of those great sea creatures that litter the beaches of most of the islands. These bones are the only real commodity of worth these isles have—which means that anyone thinking to simply sail up and pluck ivory from the shores of the Whalebones is sorely underestimating how furiously its inhabitants defend their property.