Charles Vallancey (1721-1812) was a military surveyor in the British Army eventually holding the rank of general. He was sent to Ireland where he eventually settled. He was also an antiquarian who took great interest in the history, language and mythology of his adopted country. He published a number of book on the subject which have been heavily criticised for both their content and style. He voiced the opinion that the Phoenician and Irish languages were related!(a).
Although Valancey made little reference to Atlantis, James McCulloh noted  that Vallancey was disposed to support John Whitehurst’s association of the Giants Causeway, in Northern Ireland, with Atlantis.
Richard Kirwan (1733-1812) was an Irish scientist, who had a brief (no pun intended) career as a barrister, which he abandoned in favour of his scientific interests, ending up as president of the Royal Irish Academy from 1799 until his death.
Dr. James Haines McCulloh (1793-1870) was an officer in the U.S. Army, who wrote(a) a number of books on the origins of the native Americans. In the course of his work he touched on the subject of Atlantis, or as he called it Atalantis, supporting the idea of it being located in the Atlantic in the following words;
“The speculations of Ray, Whitehurst, Buffon, Kirwan, and Pennant, upon the subject of the island Atlantis, are all in favour of its former existence, and the arguments they produce from the present appearance of the Azores, Canaries, etc., are as plausible as can be expected when the great antiquity of the subject is considered. If to their considerations our few proofs be added, it may not be presumptuous to think the tradition almost well established.” .
John Whitehurst (1713-1788) was a clockmaker and a scientist who developed our knowledge of geology and helped to promote it as a major scientific discipline. In a 1778 book, An Inquiry into the Original State and Formation of the Earth, republished in 1978 was perhaps the first writer to suggest that Ireland may have been part of Atlantis[p258].
Whitehurst was fascinated by the Giant’s Causeway in Northern Ireland and maintained that it had been created by a volcano to the north, which is now submerged. This volcano he linked with Atlantis.
*The 2nd edition of 1786 edition is now available to be read online(a).*
Ireland according to James Bramwell [0195.181], was first identified with Atlantis as early as circa 1250 AD in the Speculum Regale (The King’s Mirror)(g) which was written in Norway. Apart from that, Ireland was less controversially was first suggested in the 18th century as a possible location of Atlantis by the English geologist John Whitehurst. The idea lay dormant for over a century until the early part of the 20th century when George H. Cooper  suggested that Cork harbour fits Plato’s description of the harbour of Atlantis. Fifty years later an official guidebook claimed that one of the outposts of Atlantis was to be found on the west coast of Galway. As a nation famed for its storytelling we have never let truth stand in the way of a good tale.
The mythical Hy-Brasil was shown west of Ireland on maps as early as 1325 and incredibly, was not removed from naval charts until 1865. The UK’s Daily Star (21/5/16) with typical tabloid accuracy told its readers(f) that Hy-Brasil was off the coast of ‘Britain’!
In 1976, Steiner Books, New York, republished a book under the misleading title of Atlantis in Ireland. One may be excused for viewing this as a blatant case of exploitative opportunistic publishing. The original text was written by Henry O’Brien and published in London (1834) as The Round Towers of Ireland. Apart from being written in the rather turgid English of the period, there is not a single reference to Plato or Atlantis to be found in that volume.
Diodorus Siculus, in a well-known passage (Bk 1.158), that is claimed by some as a reference to Ireland(h), describes it as ”an island in the ocean over against Gaul, to the north, and not inferior in size to Sicily, the soil of which is so fruitful that they mow there twice in the year.” Some consider this to be reminiscent of the Platonic reference to the two crops a year gathered in Atlantis. However, I am more inclined to think that Diodorus was referring to Britain. Diodorus also mentions the Irish singular temples of ’round form’, however, this seems too early to be a reference to the round towers and more likely to be an allusion to the astronomically aligned mounds such as Newgrange, Dowth and Knowth in Ireland or Stonehenge in Britain!
In 1923, Conor MacDari, who’s eccentricity was comparable with that of Comyns Beaumont, published Irish Wisdom Preserved in the Bible and Pyramids , which among a litany of bizarre claims, proposed that Atlantis had been located in Ireland.
When Ignatius Donnelly came to the subject of Ireland, he attributed an Atlantean origin to so the various waves of settlers that came to the post-glacial island. He substitutes evidence with assertion and speculation. Donnelly further claimed that the famous round towers of Ireland are proof that the people of Atlantis settled in Ireland.
More recently Ulf Erlingsson, a Swedish geographer, insisted that with a claimed probability
factor of 99.98%, that his interpretation of Plato’s text demonstrates that Ireland was home to Atlantis . The subtitle of the book, Mappingthe Fairy Land, is probably a good guide on how seriously to take this book, particularly as it is by an author who hails from the land of the original Trolls.
In March 2008, it was reported that a Dr. Jac Hummer had mounted an expedition to South America with the intention of discovering the remains of St. Patrick under a pyramid there. But it gets better – he then explains that such a discovery will prove his theory that Ireland is Plato’s lost island of Atlantis!
Irish legend speaks of the Domnu, people of the deep sea from a land that disappeared beneath the waves. However, Ireland is still above the waves and in contrast to Plato’s statement that even in his time the location of Atlantis was marked by impassable shallows. Since sea levels have generally risen only slightly since Plato lived, he cannot have been referring to Ireland.
John Douglas Singer in his slender book, Ireland’s Mysterious Lands and Sunken Cities , has carried out an investigation into the ancient legends of Ireland and their possible connection with Plato’s Atlantis. He points out that Ireland has the greatest number of legends relating to sunken cities and islands! He draws on the works of Egerton Sykes and Lewis Spence among others.
Ireland was also nominated by Thomas Dietrich as an early colony of Atlantis in The Origin of Culture.
Somewhat incongruously, the website of extremist, Dejan Lucic, has an extensive and fully referenced article entitled The Irish Origins of Civilisation(a), including not a few controversial sources such as, Comyns Beaumont, Ralph Ellis and John Gordon.
Around 2010, a father and son team Francis J.Ward & Francis P.Ward seeminglly published their first book The Truth Against the World-Red Phoenix Rising & the Return of the Thunder Gods , in which they express the view that “Atlantis was a global, maritime empire based in Ireland”.(c)
In 2013, Skender Hushi informed the world that Albanian had been the original language of Ireland and Atlantis! Another equally odd claim came from Zoltán Simon who proposed that the ancient Hun Calendar came from Ireland [0549.147]!
Evidence for the earliest humans in Ireland is now dated as 10,500 BC.(d)(e)
*(a) See: http://atlantipedia.ie/samples/archive-2159/*
The Identity of the Atlanteans has produced a range of speculative suggestions nearly as extensive as that of the proposed locations for Plato’s lost island. However, it is highly probable that we already know who the Atlanteans were, but under a different name.
The list below includes some of the more popular suggestions and as such is not necessarily exhaustive. While researchers have proposed particular locations for Atlantis, not all have identified an archaeologically identified culture to go with their chosen location. The problem being that most of the places suggested have endured successive invasions over the millennia by different peoples.
It would seem therefore that the most fruitful approach to solving the problem of identifying the Atlanteans would be to first focus on trying to determine the date of the demise of Atlantis. This should reduce the number of possible candidates, making it easier to identify the Atlanteans.
A final point to consider, is that the historical Atlanteans were a military alliance, and as such may have included more than one or none of those listed here. The mythological Atlanteans, who included the five sets of male twins and their successors would be expected to share a common culture, wheras military coalitions are frequently more disparate.
Basques: William Lewy d’Abartiague, Edward Taylor Fletcher
Maltese: Anton Mifsud, Francis Xavier Aloisio, Kevin Falzon, Bibischok, Joseph Bosco, David Calvert-Orange, Giorgio Grongnet de Vasse, Albert Nikas, Joseph S. Ellul, Francis Galea, Tammam Kisrawi, Charles Savona-Ventura, Hubert Zeitlmair.
Maya: Robert B. Stacy-Judd, Charles Gates Dawes, Colin Wilson, Adrian Gilbert, L. M. Hosea, Augustus le Plongeon, Teobert Maler, Joachim Rittstieg, Lewis Spence, Edward Herbert Thompson, Jean-Frédérick de Waldeck,
Minoans: K.T. Frost, James Baikie, Walter Leaf, Edwin Balch, Donald A. Mackenzie, Ralph Magoffin, Spyridon Marinatos, Georges Poisson, Wilhelm Brandenstein, A. Galanopoulos, J. G. Bennett, Rhys Carpenter, P.B.S. Andrews, Edward Bacon, Willy Ley, J.V. Luce, James W. Mavor, Henry M. Eichner, Prince Michael of Greece, Nicholas Platon, N.W. Tschoegl, Richard Mooney, Rupert Furneaux, Martin Ebon, Francis Hitching, Charles Pellegrino, Rodney Castleden, Graham Phillips, Jacques Lebeau, Luana Monte, Fredrik Bruins, Gavin Menzies, Lee R. Kerr, Daniel P. Buckley.