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%.
Russian culture
Christianity, Islam, Buddhism, and Judaism are Russia's traditional religions, deemed part of Russia's "historical heritage" in a law passed in 1997.
Estimates of believers widely fluctuate among sources, and some reports put the number of non-believers in Russia as high as 16–48% of the population. Russian Orthodoxy is the dominant religion in Russia. 95% of the registered Orthodox parishes belong to the Russian Orthodox Church while there are a number of smaller Orthodox Churches. However, the vast majority of Orthodox believers do not attend church on a regular basis. Nonetheless, the church is widely respected by both believers and nonbelievers, who see it as a symbol of Russian heritage and culture. Smaller Christian denominations such as Roman Catholics, Armenian Gregorians, and various Protestants exist.