These regions have unilaterally declared their independence since the 2014 revolution/coup.
In that sense the only thing that is new is the official Russian recognition.
It's a messy situation. According to the census on wiki only 1/3 are of Russian ethnic background. Does that mean only 1/3 supported the breakaway from Ukraine?
You can't help but to make comparisons to the Sudeten Germans and the like. "Peacekeeping missions".