So in Hearthstone section there are threads explaining the origin of certain cards and how their abilities reflect where they came from.
Example: http://forums.d2jsp.org/topic.php?t=72701402&f=221

I was wondering if maybe we could compile a lore/origins of the characters in the game here.
As someone who hasn't played any Starcrafts, any Warcrafts, no WoW, and only a tad bit of D3 (but I played a lot of D2), I feel like I don't get the true satisfaction of playing with characters from other games.
Anyone else feel like this or understand where I'm coming from?
I'm willing to contribute by looking them up, or doing the entire thing myself.. so at least I have somewhere to post it.

Like, I've seen Raynor in peoples sigs before for example, but have no idea about his Starcraft lore other than he's a meh character in HotS that I would rather not have on my team.

Kerrigan had an entire expansion based on her with Starcraft and Arthas had an entire expansion for World of Warcraft
I never played anything besides Diablo 2 and 3 as well, but I know those two

I'm pretty sure there are cinematic videos on youtube that splice all the cut scenes from the various titles together to give you a good idea on the back story of everyone.