Rowbotham eventually went on to found Zetetic Societies in New York and his home country. When he died in 1885, his legacy endured through the Universal Zetetic Society, formed by Lady Elizabeth Blount. However, interest in flat-Earth theories ultimately waned following the First World War – at least for a few decades.
While it still carries elements of the Zetetic Method, modern flat-Earth theory can mostly be traced back to the International Flat Earth Research Society (IFERS), founded in England in 1956 by Samuel Shenton. The group grew in popularity in the 1970s under the leadership of Californian Charles K. Johnson. The new leader also asserted that space exploration was all a ruse to lead people astray from the Bible.