Heinrich Pudor (1865-1943) was the German author of Voelker aus altes Athen, Atlantis, Helgoland  and Völker aus Gottes Athem: Atlantis-Helgoland das arisch-germanische Rassenhochzucht- und Kolonisations-Mutterland  .
Holger Kalweit is a German psychotherapist and ethnologist and something of a conspiracy theorist. In his Irrstern über Atlantis (Inferno over Atlantis) he follows Spanuth in identifying Heligoland as a remnant of Atlantis, which he claims was destroyed in 1222 BC by the comet Phaëton.
He sees Atlantis as the home of the white Nordic people. After the catastrophe he believes that the survivors fled en masse south to the Mediterranean, where they settled in what was later known as the Levant and Greece. According to Kalweit they were responsible for the Hellenic culture, whose influence is still felt today.
At this point most people would think that his ideas were questionable enough, but unfortunately there was worse to come. He goes on to claim that the Nordic gods were also brought to Greece, “but, unfortunately, their gods were not human beings, but reptiloid aliens.” Anyone for therapy?
Horned Helmets have been worn by various warrior groups from ancient times but , in spite of popular belief, not by the Vikings. Jürgen Spanuth, the leading proponent of a North Sea Atlantis, has identified the Sea Peoples who attacked the Egyptians as North Sea Peoples. The attack was recorded by the Egyptians on the walls of Medinet Habu and where they depicted some of the invaders with horned helmets. Spanuth claimed that “The only known Bronze Age horned helmets come from north Europe”[0015.55]. The illustrations from the Danish National Museum used by Spanuth[0015.31] were more likely to have been for ceremonial use and show no signs of having been used in battle. A January 2018 article highlights a horned figure on the so-called Oseberg Tapestry, who appears to be leading a religious procession, contributing to the theory that the few horned helmets found so far were probably used for ceremonial purposes(e). Another textile fragment found at the same site also depicts a horned person, which to my mind is more reminiscent of a nordic shaman than a warrior.
>Baruch Halpern in a footnote in his paper(f) on the Sea Peoples informed us that “Sherden-like horned helmets have also been found along the northern shore of the Black Sea and on statuettes in Sardinia, but that these lack the central disks, and may reflect coincidence, appropriation, trade or migration rather than indicate a place of origin. The iconographic connections of the horns and disk would suggest devotion to a lunar god; see Bernett and Keel (1998).”<
Furthermore, he was incorrect in claiming that horned helmets were only used in northern Europe during the Bronze Age. Archaeologist Roger Grosjean (1920-1975) has demonstrated(a) that the Torreans of Corsica did use such helmets during that period. The Sherden/Shardana, considered to be one of the Sea Peoples depicted at Medinet Habu are shown as wearing horned helmets and in every instance, except three, they include a round additional piece on the crest. The Shardana are generally accepted to be from Sardinia and are possibly related to the Torreans on neighbouring Corsica. However, the Sardinian examples do not appear to have the accoutrement at the helmets’ crest depicted at Medinet Habu.
In conclusion, I think Spanuth’s horned helmet evidence is flawed but also that the Sardinian theory is not watertight. Furthermore, his core claim of an invasion from the North Sea into the Eastern Mediterranean is equally untenable. Bronze Age territorial expansion was always into adjacent or nearby territory. A journey of over 4,000 miles from Heligoland to attack Egypt makes no sense.
(c) https://www.salimbeti.com/micenei/helmets1.htm (Also see helmets2 & helmets3)
Morten Alexander Joramo is a Norwegian astrologer, musician and author. In his 2011 book, The Homer Code, he is heavily influenced by Felice Vinci, who situated Homer’s Odyssey in the northern European region. Joramo specifically identifies the island of Trenyken, in Norway’s Outer Lofoten Islands, with Homer‘s legendary Thrinacia. He also refers to the work of Iman Wilkens and Jürgen Spanuth. He also introduces the Bock Saga in support of his contention that “that there must have been an advanced culture in the high north thousands of years ago.”(a)
Although the author touches on the subject of Atlantis in The Homer Code he expands more fully on it the following year in Atlantis Unveiled. In it he again follows much of Vinci’s work as well as Spanuth’s identification of Helgoland as the location of Atlantis. He also uses Homer as well as copious extracts from Apollonius of Rhodes to justify his identification of Northern Europe as the backdrop to both the Odyssey and Plato’s Atlantis narrative.
Up to this point I found his work interesting, if not convincing. However, when I got to his ancient alien conspiracy theory and the use magic mushrooms, I cried halt.
In 2015, Joramo published The Lost Civilization of the North, which is intended to supplant Atlantis Unveiled.
Alfred Franke was a German researcher who published a review of the four main Atlantis theories of his day, fifty years ago; southern Spain, north Africa, Minoan Hypothesis as well as Helgoland, which he favoured. Franke maintained that Plato used ‘Atlantis’ as we use ‘Rome’ to indicate (a) a city, (b) an empire or (c) an area of centre of religious influence.
Rudolf Czeppan (1923-2003) was an ardent supporter of Jürgen Spanuth’s theory of Atlantis in the North Sea(a). Czeppan proposed that an impact by an extraterrestrial body south of Heligoland caused the sinking of Atlantis.
There have suggestions that Spanuth was more than a mere nazi ‘sympathiser’ and consequently had access to Ahnenerbe files relating to their Atlantis research. This might partly explain why Czeppan, a convicted neo-nazi, was so enthusiastic in his endorsement of Spanuth.
(a) https://www.vho.org/VffG/2001/4/Czeppan374-381.html (German)
Heinrich Tischner was a German Protestant minister for 32 years. He has an extensive website which includes a paper on the possible existence of Atlantis(a). He reviews the theories of a couple of German atlantologists, Otto Muck (Azores), Jürgen Spanuth (Heligoland) and finds flaws in both theories. While Tischner apparently accepts the existence of Atlantis he is disinclined to offer a theory of his own.
Deer(Greek elephos) are apparently not mentioned in his Atlantis narrative, however, he does refer to elephants (elephas). Jürgen Spanuth, who advocated a North-West Europe location for Atlantis was unable to satisfactorily reconcile his Helgoland location with Plato’s elephants. Now another German researcher, Eckart Kahlhofer, has offered a simple explanation, namely that a transcription error led to the Greek word for elephant (elephas) being mistaken for their word for deer (elephos). However, as Atlantis story originated in Egypt, what may be more relevant is the fact that the Egyptian hieroglyphics for deer (seshau) and elephant (abu) are so totally different that confusion between the two is not possible.
The elk was the largest species of deer in Northern Europe and is still found in Scandinavia. The Great Irish Deer which died out around 5500 BC was 10 feet (3 metres) tall and had an antler span of 11 feet.
Gerhard Herm was born in Germany in 1931 and studied in Munich and the United States, after which he took up journalism and filmmaking. He produced a number of television documentaries on ancient Mediterranean civilisations and has written a number of books, both fiction and non-fiction. He has had two popular books published in English, on the Celts and the Phoenicians. His volume on the Celts includes a chapter on Atlantis in which he endorses the theories of his fellow countryman, Jürgen Spanuth, who had published his views shortly beforehand supporting a North Sea location for Atlantis, although his preferred site was Denmark rather than Helgoland. Herm offers a map (p.96) suggesting that the Atlantean Empire extended beyond what is today Denmark to include part of southern Sweden and a number of Baltic islands.
Eridanus is the name of a constellation in the Southern Hemisphere as well as the name of the only Atlantean river named by Plato (Crit. 112a). It has been identified with a number of waterways(b) including the Nile (Eratosthenes), the Eider (Spedicato)(d), the Rhine(f), the Istros (Danube) of Hungary(g) and the Po (H. S. Bellamy). Mythology has fiery Phaëton crashing into the Eridanus, which means ‘early burnt’.
Adding to the confusion is the existence of the River Eridanos, referred to by
Plato (Phaedrus 229) which is a tributary of the Ilissos and still partly visible in the centre of modern Athens(e).
Jürgen Spanuth was convinced that it was as either the Elder or the Eider, which flow into the North Sea opposite Helgoland. Emilio Spedicato echoed Spanuth’s views in a number of more recent articles(c) and opted for the Eider as the original Eridanus. The similarity of the two names also adds some credence to this idea.
The late Walter Baucum quoted[183.159] the Swiss historian and geographer, Frederic de Rougemont (1808-1876), who, in his 1866 book, L’Age de Bronze, ‘proved’ that originally the Rhine had been known as the Eridanus.
Apollonius of Rhodes in his Argonautica refers to the River Eridanus as flowing into the Cronian Sea(a), generally accepted as the North Atlantic. The Eridanus is frequently referred to in ancient Greek texts as an amber rich river in Northern Europe. Amber was claimed by Spanuth to have been the Orichalcum of Plato’s Atlantis.
Kai Helge Wirth, a German geographer, has advanced the controversial theory that the configuration of the constellations were chosen to conform with the outlines of various Mediterranean and Atlantic coasts and were used as navigational aids to ancient mariners. As part of this radical idea, Wirth has pointed out that the constellation Eridanus closely follows the meandering Eider rather than the Po.
Geologists have given the name Eridanus to a river which flowed where the Baltic is now located. Claudius Ptolemy identified the River Duna, which flows into the Gulf of Riga in the Baltic, as the Eridanus.