Ironically, for a nation we will only get to see with the arrival of the Cataclysm expansion, Gilneas has a long and storied history both within the Warcraft setting and in the games that have comprised it. Colonized during the first flowering of the Arathor after the Troll Wars, Gilneas grew alongside the other colonized regions of the Arathi Empire even as the heart of that empire faltered. As proud Strom entered a period of decline, Gilneas joined other human settlements like Lordaeron and Stormwind in becoming fully independent, and a strong but insular culture developed here.
How then, did Gilneas go from one of the strongest of humanity's kingdoms to what it will be when you come to it as a player? It's said that pride goes before the fall, but for Gilneas, it could be said that pride both precipitated and delayed its fall, and that what kept it secure for decades is what ultimately brought about its current fate.
A land of frontiers
The history of Gilneas and its people is a history of self-sufficiency and pride in their very real, very notable accomplishments, born out of the expansion of the first human kingdom of Arathor. Humanity first reached the Eastern Kingdoms some time after the Sundering that tore ancient Kalimdor apart. We know that these proto-humans, descendants of the ancient Vrykul, were brought to these shores by parents who did not want to see their children murdered by exposure due to their smaller stature. These children were effectively abandoned (although at least one or two protectors must have stayed with them) in the region of the Eastern Kingdoms now known as Tyr's Hand, so named for the Watcher Tyr of the Storm Peaks, who had been a notable figure in the legends of their ancestors.
These ragged remnants grew over time into a teeming horde, then were united under the Arathi of Strom. This unified force of humans, this brawling, swaggering kingdom of rude warriors and canny warchiefs, then allied with the High Elves of Quel'Thalas and learned magic from them, soon proving every bit as talented at wizardry as they were in warfare. Together, men and elves pushed back the Amani trolls and between them, divided the continent. The elves were, for the most part, content with their magical forest to the north. The Arathi took almost everything else. It's a wonder it never came down to war with the dwaves of Ironforge or gnomes of Gnomeregan, but the inhospitable mountains these two races called home might not have appealed when so much lush, open ground was available elsewhere for humans to expand.
Humans soon filled almost all of the continent north of Khaz Modan and even expanded south to modern Stormwind. One group of settlers made its way west to an unsettled territory on a peninsula and named its new colony Gilneas. After the death of Thoradin, the great human king of the Arathor who unified humanity and led their forces during the Troll Wars, Gilneas became independent of a declining Strom, soon to lose its central position as newer human cities eclipsed its prosperity and importance. These seven human kingdoms would rise in the place of the lost Arathor Empire, and Gilneas would be one of them. While Strom's martial traditions were longer and Lordaeron larger and more populous, Gilneas was a strong frontier land with plenty of resources, a great deal of maritime trade (rivaling that of the island nation Kul Tiras), and a strong ruling house in the Greymane dynasty. It envied no nation.
Beware foreign wars
So strong and secure was Gilneas that after many centuries, when the Horde first erupted through the Dark Portal and into Azeroth, conquering Stormwind in the process, Gilneas didn't particularly care. Stormwind was far away and none of their concern, thought the average Gilnean. Even her king, Genn Greymane, didn't see any reason to be concerned. If trouble came to Gilneas, her armies would be strong enough to deal with them. He believed that the Alliance of Lordaeron needed Gilneas a heck of a lot more than Gilneas needed them, and he wasn't shy about saying so, either.
During the Second War, Gilneas was more notable for its hatred of the Horde and willingness to fight their invaders if they came to Gilneas than for any real help they gave. Following Alterac's betrayal of the Alliance and the subsequent deposing of the Perenolde family, Greymane even considered annexing the neighboring land to his own nation, as did Thoras Trollbane of Strom. While Greymane supported Lord Davar Prestor when he made his claim on the nation, after his sudden disappearance, so did Greymane's interest in the whole affair.
Eventually, disputes with King Terenas Menethil of Lordaeron and a growing desire to have Gilneas look to its own affairs led to the nation's dropping out of the Alliance following the Second War. Following that decision, and seeing the continued existance of the orc invaders as a threat, Genn decided the best way to protect his people was to isolate them entirely from both external threats and supposed allies that demanded more of Gilneas' resources than they contributed.
And so the Greymane Wall was constructed. The wall was effectively a physical manifestation of the general isolationist bent of the leadership of the nation, although it was far from wholly embraced. Many Gilneans had land and possessions outside the wall in the Silverpine Forest bordering Lordaeron and were not happy to see their farms and estates cut off from the rest of their nation.
The great grey wall of Gilneas
While this decision led to civil uprest and may even have led to a small famine if not for the efforts of Gilneans like Celestine of the Harvest using nature magics to counteract the food shortages (thus proving Gilneas was not as self-sufficient as Greymane liked to think), King Greymane failed to anticipate just how deeply some of his own people opposed his decision. Not only did the Gilneas Brigade defect wholesale from Gilneas (eventually joining Jaina Proudmoore on the trip to Kalimdor), but Greymane's old friend Darius Crowley eventually led an open rebellion against the king and his policies of isolation. As Darius has many connections in Silverpine, it's possible that some of the villages there like Pyrewood were either his holdings or those of his family, thus meaning that Genn personally injured him when he sealed the wall and closed Gilneas' ports, as he did the various merchant fleets and even pirates he trapped in Gilneas.
Darius ended up in prison before his rebellion could really get under way, but unfortunately for Gilneas, the real danger was not starvation or insurrection. Rather, isolated as they were behind the wall, the people of Gilneas had no idea what was happening to their north. Archmage Arugal of nearby Silverpine, seeing the Scourge rampaging across the whole of Lordaeron and the destruction of Dalaran by the Burning Legion, sought a force powerful enough to protect his home and found the worgen. Using the Book of Ur, Arugal pulled worgen into the woods and unleashed them on his enemies, not understanding the nature of their existence or their feral curse. These worgen would eventually run amok, killing the inhabitants of the Silverlaine family's keep.
Arugal, now unhinged either from the summoning itself or his guilt over the worgen's actions, took the place over as Shadowfang Keep. From there, the worgen curse spread southward to Pyrewood Village (a small Gilnean settlement), and from there into Gilneas itself. The curse did not stop at the wall.
Between the curse and the people falls the shadow
So in his effort to protect his people, Greymane unknowingly left them completely unprepared for what was to come. When the worgen curse turned some of their number into feral monsters, more beast than men, they spread it further, and the people of Gilneas who had always viewed themselves as self-sufficient and proud were unable to mount a defense against it. Greymane and his family were as helpless before the curse as anyone, and only through the heroic efforts of Darius Crowley and a young Gilnean hero was the city evacuated and uncursed men and women managed to escape to the countryside. Eventually, a temporary treatment was developed, but too late, as the shattering of Azeroth left many coastal sections of the country underwater.
A Horde flotilla sailed into Gilnean territory, while legions of Forsaken descended from the north. No longer would Sylvanas be satisfied with territories that were part of the rotting corpse of the former Lordaeron. She and her Horde allies would take all of the Eastern Kingdoms they could reach, even nations like Alterac, the Arathi Highlands and Gilneas that had been independent lands never part of Lordaeron at all.
Darius Crowley, now a worgen, made an alliance with night elf druids, who understood the origin of the worgen curse and could offer a means of permanently controlling it. He joined his forces to those of King Greymane for a final defense of the nation over the objection of Lord Vincent Godfrey. Ironically, while Crowley rebelled against Greymane and Godfrey supported him during the original rebellion, it was Crowley who would serve Greymane and Godfrey who would rebel, once the truth of the worgen curse and its application to the King himself became apparent. Godfrey would die for the first time after an aborted attempt to usurp Gilneas and turn Greymane over to Sylvanas' forces.
Gilneas did what Gilneans always did in situations like this. They fought, but in the end, they were outnumbered, outmatched and beset by the worgen curse as well as the Forsaken plague. King Greymane stood in personal combat with Sylvanas Windrunner, but it was his son Liam who took the fatal blow, and all Greymane and Crowley could do would be to slow the Forsaken advance and buy as much time as possible to evacuate their beloved nation. In the end, proud Gilneas became a battleground between walking corpses from an undead nation and feral man-beasts who paid for their hubris by being cursed, then displaced.
In Cataclysm, the Alliance and Horde wage constant war over the remains to determine who the true rulers of Gilneas will be, while her people are refugees, the majority now worgen, dependent on the Alliance -- an Alliance so different from the one they left that it is almost unrecognizable.
One thing is certain. Gilneans knew how to hate even before they lost their land and their very humanity. Now, revenge is their driving passion and their only goal.
While you don't need to have played the previous Warcraft games to enjoy World of Warcraft, a little history goes a long way toward making the game a lot more fun. Dig into even more of the lore and history behind the World of Warcraft in WoW Insider's Guide to Warcraft Lore.