The night elves awaken in the world and found a great society in the heart of Kalimdor. They tinker with primitive magic and inadvertently set it loose throughout the world of Azeroth.
The demonic Burning Legion, lured by the resultant energies launches a massive invasion in order to drain the world of its innate magic. The night elves, unable to defeat the raging Demons, and are forced to ally themselves with the ancient Dragons in order to banish the Legion from the world. The ensuing conflict is so apocalyptic, that the greater land-mass of Kalimdor is broken apart and smashed beneath the sea.
The night elves vow to never use magic again, for fear that the Legion would return.
Unwilling to give up its precious magics, a small band of night elves is exiled from Kalimdor. Traveling to the newly eastern lands, they found the kingdom of Quel'Thalas and begin to refer to themselves as high elves. The high elves are continually besieged by the native troll warbands.
The human empire of Arathor is founded in Lordaeron. It later expanded to also encompass Azeroth.
The high elves, on the verge of losing their continuing war against the trolls, seek the aid of the humans of Arathor. In exchange for their help against the trolls, the high elves agree to teach men in the ways of magic. The combined army of elves and humans succeeds in wiping out the majority of the trolls of Lordaeron.
The humans' reckless use of magic allows agents of the Burning Legion to find their way back into the world. The Order of Tirisfal is founded. The powerful Guardians of Tirisfal are charged with fighting a secret war against the agents of the Legion, unbeknownst to the general populace.
Internal struggles and the pressures of over-expansion cause the fragmentation of the human empire of Arathor into autonomous nations. Azeroth and Lordaeron are two.
The Guardian, Aegwynn, defeats Sargeras, the Lord of the Burning Legion in single combat. Sargeras' malevolent spirit bonds with the soul of Aegwynn's unborn child.
Though banished from Azeroth, the Burning Legion corrupts the orcish clans on the world of Draenor. The once noble, shamanistic Orc clans unite and become a rampaging Horde under the rule of the malevolent Shadow Council. By enlisting the aid of demonic magiks, the orcs were able to decimate all draenei with little loss. However the victory had its cost, and the now corrupted orcs could only think of war and bloodlust, and without an enemy to fight battled among themselves.
Aegwynn gives birth to her son, Medivh, who is destined to become the Last Guardian.
Medivh, driven mad by the spirit of Sargeras, opens the Dark Portal. He contacts Gul'dan, leader of the Shadow Council, and makes a dark deal. In exchange for the destruction of Azeroth, Medivh agrees to hand over the location of the tomb of Sargeras. The Orcish Horde begins its invasion of Azeroth.
Medhivh is killed by his best friend, Lord Lothar, and his own apprentice, Khadgar. The orc warlock, Gul'dan was in Medivh's mind at the moment of his death, and consequently suffered a vicious backlash that left him unconscious for weeks. After five grueling years of attrition, the Horde finally conquers the nations of Azeroth and Khaz Modan, and claims Blackrock Spire as its base of operations.
Blackhand, the Horde's current warchief, was slain and succeeded by Orgrim Doomhammer. Doomhammer disbanded into groups of Raiders who were thought to be loyal to Blackhand. By torturing Gul'dan's spy, Garona, Doomhammer, located and slaughtered the Horde warlocks. Gul'dan was forced to bow to his new superior. To gain Doomhammer's trust, he slaughters his own Necrolytes, and used their spirits to create Death Knights.
Lord Lothar leads an exodus of refugees to the northern nation of Lordaeron. Once there, he convinces the leaders of the seven Human nations to unite in arms against the Horde. The separate nations of the Arathorian empire are reunited as the Alliance of Lordaeron. Through the chaos, Thrall was born. This young orc was found and captured by humans, and raised as a slave and gladiator.
Orgrim Doomhammer, the Warchief of the Horde, launches his mighty fleets to invade the shores of Lordaeron. The unstoppable Horde pushes its way into the heartland of Lordaeron and succeeds in destroying the High Elves' ancient kingdom of Quel'Thalas. Gul'dan attempts to free Sargeras. Orgrim discovers the plan and kills Gul'dan.
The Alliance forces push back, but Lord Lothar is killed during the siege of Blackrock spire. Spurred by the death of their beloved leader, the Alliance armies crush Blackrock Spire and push the Horde back to the threshold of the Dark Portal. The Dark Portal is destroyed by Khadgar and the Horde is defeated. The renegade orcs are rounded up and placed into internment camps by the Alliance.
The ancient orc shaman, Ner'zhul, rallies the few clans still left on Draenor and reopens the Dark Portal. He orders his clans to steal a number of artifacts from Azeroth that will allow him to open multiple Portals in Draenor. The Alliance sends its armies, led by the wizard Khadgar, through the Dark Portal in order to stop Ner'zhul's schemes. The two armies clash throughout the hellish world of Draenor for months.
Empowered by the stolen artifacts, Ner'zhul opens a number of portals in Draenor. Yet, before he can lead his clans through them, their energies spiral out of control and begin to destroy the very fabric of that world. The Alliance heroes, knowing that they would be trapped forever, are forced to destroy the Dark Portal so that Azeroth is not consumed by the raging energies.
The blasted world of Draenor tears itself apart. The Alliance grows uneasy as the orcish internment camps are reopened. Only a few, scattered orc clans evade the Alliance's wrath and eke out a living in the harsh wilderness.
Thrall, a young orc raised as a human slave and gladiator, escapes from bondage and sets off on a quest to discover his stolen heritage. Thrall succeeds in reuniting a number of renegade orc clans and leads them in revolt against the Alliance Regional Wardens. With the threat of a new Horde looming over them, the Alliance nations begin to bicker and quarrel. Tensions run high amongst the human leaders.
Thrall becomes the new Warchief of the Horde and helps to reintroduce his people to their abandoned shamanistic culture. The reinvigorated Horde finally begins to lose the last traces of the Legion's demonic corruption. Civil strife rages through the nations of the Alliance as threat of a new, unseen foe draws near - The Burning Legion returned.
Without the Guardians of Tirisfal, human forces begin to crumble. The night elves at Kalimdor sense the disturbance and feel that they are somehow responsible. [Warcraft 3 begins.] Ner'zhul returns as a Lich King, who has long transformed his loyal followers into minions of the living dead. Named by others as the Scourge, Ner'zhul takes hold of frozen continent of Northrend. From here he seeks to rule a world of the dead.
Prince Arthas rides forth to battle the Scourge and instead falls prey to the cursed blade Frostmourne. He becomes one of the most powerful Death Knights and rides out to bring a plague to his own people of Lordaeron. After killing his own father, Arthas is lead on a series of tasks until at last the Alliance is formed at the promptings of the prophet Medivh and the Burning Legion's connection to the Well of Eternity is cut off forever.
After 10000 years of being imprisoned, Illidan is set free. At the behest of Kil'jaeden, he sets off to destroy the Frozen Throne in order to destroy the Lich King. He is thwarted in his plans by his former jailer Maiev and fails his mission. After being recaptured and then set free again. Illidan sets out to destroy the Lich King once more. The Lich King, sensing his danger as he is imprisoned in his frozen throne, calls Arthas again.
Arthas manages to outmaneuver Illidan and uses Frostmourne to shatter the icy throne freeing the helm and breastplate of the Lich King. Donning the armor, Arthas merges with the old Lich and becomes the new Lich King. An uneasy truce between the Horde and the Alliance is reached as both sides move on to lick their wounds and rebuild.
The orcs leave for Kalimdor to resettle in a new land. Jaina Proudmoore resettles on the coast of southern Kalimdor. Grand Admiral Daelin Proudmoore arrives with a large armada looking for survivors. His hatred for the Horde is great and he sets against them once more only for his own daughter, Jaina Proudmoore to set herself and her forces against him. The orcs allow Jaina Proudmoore to resettle in peace, but tensions are still there.
Timeline originally published by Blizzard in the Warcraft I manual (1994), with further dates established from the Warcraft II manual (1996), Beyond the Dark Portal manual, and Warcraft III manual. Also includes dates mentioned in the RTS games themselves.