All the while told that their soul is gone, their minds belong to the Lich King. Souls of the fallen heroes of the Alliance and Horde, ripped back from death and reinserted into their own bodies, turned into Deathknights. The last, and current, generation is the one the PCs play. Originally they never really got resurrected, but kindof eased into undeath as they made the transition. (Again, there are exceptions *cough*Zeliek*cough*) Amongst others, Baron Rivendare ~and~ Mograine are actually part of this generation of Death Knight. These were humans who received powerful magical armor and weapons that would slowly corrupt them from the inside-out. Technically by the Lich King by proxy, but still not the ones that the players get to use. The second generation of Death Knights were human warriors/soldiers/leaders tempted with power by Kel'Thuzad. Do recall he fights with a ginormous mace, that's a cudgel of sorts. Although he still had a cudgel as part of his focus of power. Teron Gorefiend is part of this first generation and one of the few, very few, in which this process actually properly worked. Usually the soul was stuck in the cudgel each Death Knight had on him, because the guy who made them wasn't all that good at it and found that most of them just re-died if he stuck the souls in the bodies directly. The first generations were fallen human hosts with the souls of orc warriors/necromancers controlling them. If I recall correctly, there are 3 generations of Deathknight. You could loathe what you were, or embrace a new destiny. Of course you may just give into it all and enjoy cleaving through whatever someone asks you to. there is a lot of potential burden, and also a lot of potential for one to seek redemption. You may be triply cursed if you were serving the Dark Horde, who served Nefarian. Mannoroth's Blood curse has been lifted, but the memory and aftermath still stains the soul of every Orc. Regardless of your prior allegiances, you are now doubly tainted with demonic and deathly power. Lets you be second gen (those raised during the fall of Lordaeron and Quel'Thalas and possibly during the events of nilla and maybe TBC) or third gen Lots of options for political RP within the forsaken structure as either way you will not be trusted, not that forsaken are trustworthy anywayДЇorsaken tend to have a general detachment from life (as they are undead) though they may continue to go through the motions of normal mortal attachment, this has obvious RP implications Let's you be 'first gen' (ie WC2) DK through third gen DK (Those raised just prior to and through the WotLK era)Д¬ould RP as an original member of the scourge who became a DK (most likely through strong memory/mental factulties)Д¬ould RP as a Forsaken whose will became weak and rejoined the scourge A lot depends on where you want to RP in the timeline. You can also be more recently converted as one who went to the plaguelands for blood and honor, or even after the Wrathgate incident as one of those Thrall sent to 'help' Sylvanas. Perhaps you were living in a remote area, perhaps you were of the Dark Horde (those currently in Blackrock mountain), there are several options there. As an Orc you can be one of those who were unable to be liberated by Thrall when he liberated the internment camps. As a Forsaken racial choice you can be one of the original scourge or a Forsaken who slipped back into the Lich King's control. The Lich King has been gathering warriors since WC3 (it is implied that Arthas is not the only DK in Ner'Zul's service. Your character need not be bloodthirsty to be corrupted, despair in the face of the horrors of daily life on Azeroth is more than enough to make one submit to the Lich King's mental prodding.ДЄssuming you want to make a scourge-based DK you have a lot of options. As with Arthas and Darion, they need only be corrupted. Death Knights of the Scourge do not need to have died. As has been mentioned though, these were orc spirits put into dead human bodies, and so a human or undead race selection would be most appropriate.Дў. Affliction warlocks are also a good choice should you be looking for this particular lore option. That technicality aside you can roleplay one fairly effectively, particularly if you are unholy spec, as a DK class. They were essentially warlocks/necromancers. The first 'Orc' Death Knights are not like the current class. Several people are mentioning lore out of context (but with good intent).ДЎ. I think a couple of clarifications are needed.

Warcraft 2 death knight