LocationFlandrensis is located on five small islands of the coasts of West Antarctica: Siple Island, Cherry Island, Maher Island, Pranke Island and Carney Island and based its claim on an interpretation of the Antarctic Treaty (1959). The founder of Flandrensis sent letters to the United Nations, the European Union and to the nations who signed the Antarctic Treaty to inform them of this claim. All of these countries ignored the claim of Flandrensis. Flandrensis has no intentions to visit their claims.

Because of the claims, a diplomatic conflict with the micronation Westarctica arose in 2010, this resulted in the creation of the intergovernmental Antarctic Micronational Union (AMU). In 2010 the Russian newspaper Chastny Korrespondent published an article about Antarctic micronationalism and described Flandrensis as one of the most resonant micronations on Antarctica.

Siple Island is a 110 km long snow-covered island lying east of Wrigley Gulf along the Getz Ice Shelf off Bakutis Coast of Marie Byrd Land, Antarctica. Its area is 6,390 km² and it is dominated by the potentially active shield volcano Mount Siple, rising to 3,110 m making this the 17th ranking island in the world by maximum altitude. Carney Island is located between Siple Island and Wright Island along the coast of Marie Byrd Land, it’s an ice-covered island, 110 km long and about 8,500 km² in area. Nearby are located Maher Island, Cherry Island and Pranke Island.