And when in secure power, the socialistic overlords magnanimously allowed "freedom of religion" all the while covertly intent on undermining Christianity.
The plan was to lure inquisitive religious people into the thinking of the communists. Of course, that was easy since the entire social milieu was essentially owned and operated by the State. Repress freedom of the press, spy on worship services, control the major means of production and promote State-loyal workers and the pressure on Christianity multiplies one hundred fold beyond what atheists even feel today in America.
Over the decades in the USSR there was a general attempt to stamp out religion by withholding educational and job positions, control or closing of religious locales, imprisoning dissenting clergy, and atheistic requirements for Party membership
Shawn Mathis (the Denver Christian Apologetics Examiner) provides an insightful article on the relationship between atheism and communism here. I encourage you not only to read this article but his other posts as well... they are very good! While as Mathis points out at the end of this article atheists today are not guilty by association and that atheists today use a more democratic approach, at the same time the items mentioned are noteworthy - for similarities exist on some levels today and we do not want to repeat history in the areas mentioned. The way to avoid this is for Christians to be informed of the past.