The folks in Eastern Ukraine have watched the US/EU backed radicals overthrow a democratically elected President and they're fed up with all the Western interference in their lives.
They're going to decide for themselves how they want to be governed, and if the radicals in Kiev don't like it, they'll be dealt with accordingly.
"Decide for themselves". Ya, right. Soviet agents are in there now acting as provocateurs. Hopefully Kiev goes in soon and kicks their asses out of the Ukrainian building they are squatting in.