Eastern Ukraine
According to a 2016 survey of religion in Ukraine held by the Razumkov Center, 73.5% of the population in Eastern Ukraine were Christians (63.2% Eastern Orthodox, 8.1% simply Christians, 1.0% Protestants, and 0.3% Latin Rite Catholics), 0.5% were Muslims, 0.3% were Jewish, and 0.3% were Hindus. Not religious and other believers not identifying with any of the listed major religious institutions constituted about 24.7% of the population. It also showed that approximately 55.6% of the population of eastern Ukraine (which in Razumkov's mapping excluded Donbass and consisted of the regions immediately to the west of it) declared to be believers, while 13.4% declared to be undecided or non-believers, and 3.5% declared to be atheist. 
A 2007 survey by the Razumkov Centre asked "Would you like to have your region separated from Ukraine and joined another state?" In eastern Ukraine, 77.9% of respondents disagreed, 10.4% agreed, and the rest were undecided. 
In a poll conducted by the Kyiv International Institute of Sociology in the first half of February 2014, 25.8% of those polled in East Ukraine believed "Ukraine and Russia must unite into a single state", nationwide this percentage was 12.5%.
Religion in Belarus
Religion in Belarus has been traditionally Orthodox Christianity although there is also a sizeable Catholic minority. The legacy of the state atheism of the Soviet era is evident in the fact that a large part of the Belarusians are not religious. Moreover, other non-traditional and new religions have sprung up in the country after the end of the Soviet Union. According to the most recent data published in 2011 by the Ministry of the Interior, 48.3% of the Belarusians are Orthodox Christians, 41.1% are irreligious (atheists and agnostics), 7.1% are Catholics, and 3.5% are members of other religions.