Kind of true. Kind of not. Take a look at this map and brief explanation.
http://northhistories.blogspot.com/2014/09/pereyaslav-treaty-of-1654-agreement.html
The point is that Ukraine was very much divided on affinity with Russia. To the east (the regions Russia has so far concentrated on occupying) half or more of the population considered themselves to be, fundamentally, ethnic Russian: basically colonists FROM Russia at the time Russia stepped in.
There's this American fantasy, propagated by our MSM, our NeoCons, and our ignorance, that Russia simply "invaded" the Donbas (eastern Ukraine) out of greed. The truth is, that most of those people were probably delighted when Russia first came in -- because they were being massively unrepresented and actually oppressed (including murdered) without any legal redress under the Ukraine government.
Don't we believe in "no taxation without representation" anymore? That people who are systematically oppressed by their RULERS have a "God given right" to break away and form their own country? Once upon a time that is how the Colonists came to break from England. What is so hard to understand about that?
To those of us who have never known anything but the semi-stable nation-states it can be hard to understand that there didn't use to be “countries” as we know them now. There were ethnic groups. From time to time migrant ethnic groups would "migrate" their way in, generally after having been displaced by famine, war, or sometimes as a direct consequence of conquest.
And sometimes it was actually a religious divide amongst a single culture.
However it happened, intermarriage or effective bans on intermarriage, would produce new classes, subcultures, differing preferences or trades, and eventually language differences. Most of these reconfigurations were not exactly "voluntary", much less "democratic".
If you think back, I expect you can remember when there were significantly strong divisions within the United States. Remember when the "Southern accent", the Bronx accent, the Boston Accent, the midwestern accent, etc. were real things?
How many people realize that the Revolutionary war produced a massive break amongst the population. A large portion of the population in the colonies didn't WANT to break away from England!
After the war ended, a lot of colonists felt, or were, compelled to move:
American immigration to Canada dates back as far as the Revolutionary War, when approximately 100,000 Americans fled north. The majority of this total were colonists loyal to the crown, and their arrival north of the border led to massive changes to the social, cultural and political landscape of Canada for generations to follow.
Similar to the colonists who left the newly formed United States in the 18th century, thousands of black Americans departed the USA for Canada during the 19th century in order to avoid the horrors of slavery and racial oppression during the War of 1812 and the subsequent Civil War. Unfortunately, although many found freedom in Canada, significant numbers of black Americans still encountered economic prejudice and social discrimination after arriving in Canada.
The 20th century also saw thousands of Americans move to Canada to avoid conscription to the U.S. army during the Vietnam War. According to Statistics Canada, in the nine-year period from 1966 to 1975, almost 240,000 Americans moved to Canada.
http://moving2canada.com/planning/moving-from/united-states/history-american-immigration-to-canada/
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