Seventh-day Sabbath as a Sign of Christian Loyalty: The Seventh-day Adventists in the Conflict with Totalitarian Regimes in the 20th Century Czechoslovakia. The subject matter of this article is to describe and analyse the conflict between the Seventh-day Adventists and totalitarian regimes in Czechoslovakia. It explains the reasons why the clash occurred, with specific emphasis on the role the Sabbath (Saturday) observance plays in the Adventist theology, and eschatology in particular. There are some cases of persecution due to the Sabbath observance during the time of National socialism, however the conflict intensified especially during the 50s and 60s, when a number of Adventists were imprisoned. There were two points of conflict, namely mandatory military service and school attendance. The school attendance issue disappeared in 1968 when two-day weekend was introduced in Czechoslovakia, however Adventist soldiers struggled even in the 70s and 80s. The whole problem disappeared only after 1989.