“I think Ukraine, with the support of the European Union, is in a position to fight and WIN all of Ukraine back in its original form,”
The original form: 
Remove the yellow part east of Dnepr and it start looking roughly like what I'm expecting when the dust settles.
Have to ask, why 1654 specifically?
It is the date of the Pereiaslav Agreement in which the Zaporozhian Cossacks declared fealty to Tsar Alexis Romanov and in exchange recieved partial autonomy and protection after the bloody uprising period and failed bid at independence started in 1648. It's important date because it's first time something that can be more or less correctly called Ukrainian polity was founded.
Much obliged, thanks!
Man will I not miss this country (or region in general) once I can leave. I really hope the EU won't make us fight until everything here is turned to dust...
Are you in Ukraine?
yes I fucking hate it here.