In the religious sphere, atheism was officially promoted and taught.
British Dictionary definitions for atheism
atheism
/ˈeɪθɪˌɪzəm/
noun
1.
rejection of belief in God or gods
Word Origin
C16: from French athéisme, from Greek atheos godless, from a-1 + theos god
Word Origin and History for atheism
n.
1580s, from French athéisme (16c.), from Greek atheos "without god" (see atheist). A slightly earlier form is represented by atheonism (1530s) which is perhaps from Italian atheo "atheist." Ancient Greek atheotes meant "ungodliness."