The gilded domes and spires of Monmurg are a testament to the Sea Princes one time profession: piracy. The ancestors of the current princes ranged as far as Relmor Bay, taking ships, maidens, and other forms of plunder whenever they could find it. Especially bold captains might even land near an isolated town and attempt to sack it, carting away wonderful treasures and many slaves.
Today the princes have mostly exchanged piracy for more "legitimate" enterprises. Their ships still reach the same ports and even head to those beyond the Flanaess but rather than swordsmen they are filled with exotic goods and shrewed merchants. This change occurred after the famed battle of Jetsom island, though one should not think that this put an end to piracy in the region. The princes support privateers, issuing letters of mark to any who promise not to attack ships bearing the princes' coat of arms. Many ships from the other nations of the Flanaess will often hang the Sea Princes' colors in order to avoid such attacks. On rare occasions a Sea Prince might lead his personal fleet out on a raid if he believes some particularly lucrative prize might be won.
Though most of the princes' trade is fairly conventional, they are also the largest exporter of slaves in the whole of the Flanaess. Most of these are taken in raids across the Hool Marshes into the Yeomanry, and sometimes even Keoland. This has made the Sea Princes wildly unpopular in those areas, but their mercenary armies and massive fortifications are more than enough to stop most invaders. Couple that with the fact that their fleet could easily prevent any sea based invasion, and the inhospitable nature of the Hool marches and it's easy to see why the Sea Princes still exist as a separate entity despite their nefarious nature.
Their capital of Monmurg is truly a sight to behold. Despite it's small size when compared with cities such as Greyhawk, Monmurg's splendor may be without equal on the continent. It possesses great onion domed palaces covered in turquoise and precious metals, many spired temples to the various gods whose cults the sailors brought with them after their many excursions, and slaves and citizens from all the four corners of the world. Mahogany from the southern continent and precious metals from beyond the Sea of Dust fill its markets. It is no wonder that so many adventurers make it here to find work or plunder.
Natives of the Hold dress in an ostentatious manner that is often made sport of by those from other kingdoms, especially Keoland and the Yeomanry. Layers of silk, bejeweled turbans, jade masks, peacock feathers, and other even more bizarre wares find there way into these outfits, often all in the same one. Still, the Sea Princes are fierce warriors, even if the bulk of their armies is composed of mercenary fighters. This is solely due to the low population of natives rather than an inability to fight. Some of the finest swordsmen in the world are from the Hold, and a person who forgets this is likely to lose a limb or two.
The Hold of the Sea Princes is ruled by Prince Medardo of Monmurg, Captain of all Fleets and Ruler of the Azure Sea. He demands that the other magnates of the Hold spend most of the year within their palaces in the capital so that he might keep a close watch on them. Most obey, but the Plar of Hool often ignores this command. He spends his time in a fortress on the southern side of the Hool Marshes where he oversees the slave trade. Some rumor that Prince Medardo would like to end slavery in the Hold, but that Plar Enrico is violently opposed to it. There are even those who say the Plar is responsible for the recent attempts on Medardo's life, but this is utter nonsense. Surely the Prince would have retaliated by now if this were the case.
And thus I present one of the other candidates for the PC's home base. I don't really have much more to say about this entry, but I do wonder how closely this and my interpretation of Shield Lands mirrors the official one.