Maausk, meaning roughly the faith of the land, is organised in Estonia as Maavalla Koda and presents itself not as a revival but as a continuity: a set of practices attached to particular places that persisted alongside nominal Lutheranism because they were never wholly displaced. The claim is contested by historians of religion, who point out that the movement took its present organised form in the twentieth century and that continuity of practice is easier to assert than to demonstrate. What is not contested is that the places are real and old.
The central category is the hiis, a grove or hill treated as sacred and left unfelled, and the associated springs, stones and single trees where offerings were made. Ethnographic collection in the nineteenth and twentieth centuries recorded hundreds of them across the country, along with the rules that went with them: nothing is cut, nothing is removed, and what is brought is left.
The interesting part is legal rather than doctrinal. Estonia has treated these sites as heritage rather than as private religious property, and an inventory programme was undertaken to identify and map natural sacred sites so that they could be considered in planning and forestry decisions. That places the state in the position of protecting the material remains of a religion whose adherents are a small fraction of the population, on the grounds that the groves belong to the national record.
Conflicts follow from exactly that framing. Where a road, a quarry or a felling licence has met a mapped hiis, the argument has been between heritage protection and development rather than between one religion and another, and Maavalla Koda has fought those cases through the planning system.