Tensions continued to rise between the Horde and the Alliance, until the point in the timeline that World of Warcraft was launched. Four years after the events at Hyjal, one year after the formation of the Burning Blade, the drums of war thundered once more -- despite Thrall and Jaina's wishes for peace. In World of Warcraft, the struggles and tensions that arose were largely due to struggles over land -- the orcs encroachment into Ashenvale, the fighting between the last of the Kul Tiras fleet and the orcs of Durotar, the struggle between the tauren of Mulgore and the dwarven archaeologists that wanted to survey their lands, the fighting between the remaining humans in the northeast, and the Forsaken that had taken hold in Lordaeron. Each side had their own challenges they were facing from within as well.
For the Horde, it was the continued presence of Rend Blackhand, who proclaimed himself the 'true' leader of the New Horde of Azeroth, as well as the disturbing revelations about Blackrock Spire. The reason Rend was able to make these claims was because he had protection in the form of Lord Victor Nefarius, or Nefarian, son of Deathwing. Nefarian was charged by his father to oversee Blackrock Spire and make sure the orcs stayed firmly within the black flight's control. This plan was successful to a large degree -- the Dark Iron dwarves of the mountain had been pushed down into Blackrock Depths, while Nefarian and the supposed 'New Horde' ruled the spires above, something that would've been largely impossible without the contribution from the Black flight.
Beyond this, it was revealed that the Black flight had other plans -- that the brood mother, Onyxia, was attempting to take down the Alliance from within. Rather than simply letting the black flight destroy the Alliance, Thrall instead charged his people with destroying the black dragon. Partially because having a black dragon around wasn't the best idea in the world, but mostly because again, he did not wish to return to the wars and the fighting of years past, he wanted peace. Make note of this, we'll be addressing it again shortly.
When both Onyxia and Nefarian had been taken care of, a new problem arose -- the Qiraji of Silithus had awoken for unknown reasons, and threatened the very fate of Azeroth itself. The Horde united, working together to prepare for the assault and the second War of the Shifting Sands. Thrall appointed Varok Saurfang as Supreme Commander of the combined war effort, and the Horde drove into Silithus and fought back against the Qiraji and their leader, the Old God C'thun. The victory was short lived when news from the east arrived -- the Scourge were making their move, the dread citadel Naxxramas had appeared above the Eastern Plaguelands, and the lich Kel'Thuzad was threatening... you guessed it, all of Azeroth.
After Kel'Thuzad's defeat, things quieted down once more. The Alliance and Horde were still fighting with each other, though they'd often been fighting the same battles -- the Alliance were just as concerned with Onyxia, Nefarian, C'thun, and of course Kel'Thuzad. Neutral factions such as the Cenarion Circle, home to both the night elf and the tauren druids, and the Argent Dawn of the Plaguelands, who refused to step into the politics and fighting between the Alliance and Horde factions, promoted peace between the factions, taking the side that Jaina and Thrall had mirrored -- there were simply too many enemies and dangers in the world to waste time fighting with each other.
Unfortunately, there were few that shared that belief. Some time after Naxxramas' defeat, the world was thrown into chaos again -- in the form of the draenei survivors from the broken world of Outland who hurtled abruptly into the Azuremyst Isles. For the Alliance, this represented potential new allies -- but for the Horde, and particularly the orcs, this was bad news. Why? Because the orcs of Draenor, back in the days of their original corruption by the Burning Legion, had slaughtered a good 80% of the draenic race in cold blood, driven to do so by the demonic bloodlust that had tainted their veins and the mind of their leader. In addition to this, the Horde received a new set of allies of their own -- the Blood Elves, former High Elves that had turned from the Alliance due to the Alliance's staunch refusal to aid the shattered people after Silvermoon was attacked by Arthas, and the Sunwell, source of their power, summarily destroyed after Kel'Thuzad's resurrection.
The blood elves were an odd sort of ally to choose, but they had the full support of Sylvanas, a former ranger of Silvermoon, now Banshee Queen of the Forsaken. Thrall had his own reasons for bringing the blood elves into the Horde – not only were the elves and their curious addiction to magic eerily reminiscent of his own people's struggle with the fel taint of the Burning Legion, but the blood elves had established a foothold in Outland. Thrall was keenly interested in Outland -- the homeland of his people, the home that he'd never seen, nor set foot on. The Warchief wanted to try and locate the remains of the native orcs of Draenor if at all possible, and with the help of the Blood Elves, it looked like this just might be possible.
After establishing a foothold in Hellfire Peninsula those remains were indeed found. While Hellfire and indeed a large portion of Outland seemed to be overrun by the tainted fel orcs that had fallen under the Burning Legion's sway, a small offshoot of orcs remained that were unaffected. These orcs, who called themselves the Mag'har, or 'uncorrupted' in orcish, never entered into the original blood pact with Mannoroth. Prior to the blood pact, a disease known as the "red pox" had spread throughout the Horde, and orcs that had come down with the illness were sent to Garadar, a quarantine village in Nagrand, to recover. Brown skinned and lacking any fel taint whatsoever, the Mag'har continued to survive even after Draenor was shattered, steadfastly adhering to the old ways.
Thrall rejoiced -- for here were the people that he had been looking for, orcs that his Horde could look up to and follow. Not only were the Mag'har a peaceful sort, there were several familiar names in that little village -- Dranosh Saurfang, son of Varok. Jorin Deadeye, son of the chieftain of the Bleeding Hollow clan. And another orc who went by the name of Garrosh Hellscream, son of Grom Hellscream, leader of the Warsong clan and beloved friend and mentor to Thrall.
Garrosh led the small Mag'har encampment of Garadar alongside Jorim Deadeye, overseen by Greatmother Geyah, who had fallen ill. This worried Garrosh terribly -- having been sent to Garadar when he was but a boy, the orc knew little of his father. What he did know was this: Grom lusted for power like no other, and despite being aware of this weakness, he still drank Mannoroth's blood, and bound Hellscream and the other orcs of the Horde to serve under Mannoroth. This knowledge deeply troubled Garrosh, and he was not only ashamed, but convinced that he was doomed to repeat the mistakes of his father. Garrosh knew that when Greatmother Geyah passed, he would be expected to take over leadership of the Mag'har, but he was afraid that this responsibility would only spell doom for the one remaining uncorrupted tribe in Outland.
It was the arrival of Warchief Thrall and his subsequent meeting with Greatmother Geyah -- who was none other than the Warchief's grandmother -- that finally lifted the depression that plagued Garrosh. After learning of the beliefs that Grom's son held, Thrall showed him what had happened after Grom and the others had left Outland for good, what had happened after the trip to Kalimdor -- the battle between Grom Hellscream and Mannoroth, Grom's success in freeing the orcs from the blood pact, his death, and Mannoroth's. Garrosh, suddenly confronted not with a father to be ashamed of, but a father with a reputation to be lived up to, gained a tremendous amount of strength and confidence due to Thrall's intervention.
This is, incidentally, where all hell starts to break loose for the orcs of the New Horde.
Whether it was out of kindness, out of respect for the father that he never knew, or out of a desire to show the orcs of the New Horde the ways of the peaceful Mag'har in an effort to illustrate that the peace he'd been striving for was not something so far-fetched for orc society, Warchief Thrall brought Garrosh Hellscream back with him to Orgimmar as an advisor.
This is probably the worst decision Thrall has ever made.
Garrosh immediately began to clash with Thrall's way of thinking and his peaceful ideals, continually questioning Thrall's reasons for peace and suggesting that war with the Alliance was the only option a true leader would ever consider. This culminated with a clash of truly epic proportions, as the Lich King's forces loomed ever closer just before the Wrath of the Lich King:
Garrosh Hellscream challenged Warchief Thrall, and Garrosh won. Before this could be addressed, the Herald of the Lich King arrived with a full force of Scourge to attack Orgrimmar. After their defeat, Thrall was left with a choice. He could keep Garrosh in Orgrimmar as he had planned, wait and see what the Alliance was doing, attempt to unite the Horde and Alliances efforts and risk being overthrown by the impetuous son of Grom Hellscream, or he could send Garrosh away as he wished, to Northrend. Thrall chose the latter of the two options, sending not only Garrosh, but also Varok Saurfang to keep an eye on Hellscream and his efforts up north.
Saurfang did as was asked of him, reporting Hellscream's activities to the Warchief and keeping the reins firm on the younger Hellscream's desires. In the meantime, Thrall worked to keep the ever-dying ember of peace alive. This proved difficult as the King of Stormwind, Varian Wrynn, held no love for the orcs whatsoever. It was his father who had been murdered before his eyes at the hand of the half-orc Garona, it was his mentor and second father who had been murdered by the orc Orgrim Doomhammer with the same weapon that Thrall now carried. It was Thrall's other advisor, Rehgar Earthfury, that had forced Varian into years of service as a gladiator, meat to be bet upon and shuffled around like so much cargo in the gladiatorial arena fights. From Varian's standpoint, there was very little to be trusted about the orc race -- especially not when their leader couldn't even seem to keep hold of his people, instead ordering them to stand down at every turn.
For while Thrall spoke of peace, of alliances, the orcs of the New Horde were busy doing what orcs do best -- fighting. With the events of the Wrathgate and the summary betrayal by Grand Apothecary Putress and his renegade branch of the Forsaken, it seemed as though whatever tentative peace Jaina and Thrall had fought for was destroyed. And when dark forces beneath Ulduar were discovered, that peace was shattered utterly.
King Varian Wrynn had had enough -- and so had Garrosh Hellscream. Future efforts to promote peace between the two factions proved futile, even Tirion Fordring, Supreme Commander of the Argent Crusade could not bring the two sides together to unite as one and destroy the Lich King. The battle against Icecrown Citadel was not only a battle between Horde forces and the Scourge, but the Alliance forces that also sought the Lich King's demise, culminating in an airship battle as both sides raced to Icecrown Citadel's peak.
It is here that the current situation stands: Horde and Alliance, at each other's throats. Despite one small display of compassion to a father who had lost his only son, King Varian is still dead set against an alliance with the orcs responsible for so many of his people's deaths. Thrall's hold over the orcs as Warchief is rapidly slipping from his fingers, and Garrosh Hellscream is chomping at the bit to take over. But what happened? How did Thrall, son of Durotan, fall into such disfavor with his people, when he worked so hard to raise them out of their depression and show them what a noble group of people they could be?