Marxism-Leninism
While Marxism–Leninism is usually described as an ideology rather than religion, many communist states placed importance on the preservation of the remains of their respective founders, and making them available for veneration by citizens. In both the Soviet Union and the People's Republic of China the mausolea of, respectively, Lenin and Mao Zedong were the focal points of the two nations' capitals. The communists did not rely on the natural incorruptibility of the remains, but used an elaborate embalming process to preserve the lifelike appearance of the bodies.
Minor communist nations would often seek the help of the USSR or PRC to preserve the remains of their own founders in a similar way to how it was done in Moscow or Beijing. See Georgi Dimitrov Mausoleum (Bulgaria, 1949), Ho Chi Minh Mausoleum (Vietnam, 1973), Kumsusan Memorial Palace (North Korea, 1994). The bodies of the founders of the socialist Czechoslovakia, Mongolia, and Angola were also at some point made available for display and veneration in similar mausolea.
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