Tabachnyk's view of Ukraine's history includes the thesis that western Ukrainians aren't really Ukrainian.
About 600,000 Western Ukrainians were arrested between 1944 and 1952, with one-third executed and the remainder imprisoned or exiled to the east.
Its leader, Andrey Sheptytsky, was seen as a "father figure" by most Western Ukrainians.
Furthermore, Soviet partisan activity threatened to become the major outlet for anti-German resistance among western Ukrainians.
In response to a question gauging tolerance of Russians, 15% of Western Ukrainians responded positively.
The movement was particularly supported by western Ukrainians' largest and most significant political party, the Ukrainian National Democratic Alliance.
Furthermore, western Ukrainians retained their own Ukrainian Galician Army and government structure.
Those Western Ukrainians used the name Rusyny (Ruthenians) prior to the national revival of the 19th century.
This influence was so great that western Ukrainians were accused of wanting to create a theocracy in western Ukraine by their Polish rivals.
Tabachnyk is loathed by opposition politicians for his view of Ukraine's history which includes the thesis that western Ukrainians aren't really Ukrainian.