Andreas Möhn

Andreas Möhn (born 1964) is a German freelance writer and editor. He first used the pseudonym "Lalaith" and now uses the pseudonym "Codex Regius" together with his wife, Metka Klemenčič.

He has an on-line presence concerning the study of Tolkien's Arda by participating on the Tolklang and Tolkien Mailing Lists. His website, Lalaith's Middle-earth Science Pages, is centred on more obscure aspects of the legendarium and scientific reasoning on several information Tolkien gives out. His essays concern Mannish tongues, calendaric calculations, and various geographical topics of Arda.

In October 2014 some of the articles were removed from the site, and were updated and provided as purchasable books. By 2016 the Science Pages were moved to another site as blog articles. The content of the books about Middle-earth largely replicates the articles from Lalaith's Middle-earth Sciences page.