Apparently so, according to this Danish site (Aug 16, 2017, written by Ben Hamilton):
Caesar conquering Britain a 9th century invention by Alfred the Great: Saxon king fabricated 54 BC invasion to replace Viking-friendly heir and protect England from the Danes
He came … He saw … but He tampered
As you do.
This story is by a certain “Rebecca Huston, a former National Geographic Channel producer and American screenwriter who after ten years of original research and analysis” concludes that “by doctoring a Latin version of one of the ancient world’s most famous writings, and altering several Old English manuscripts, he was able to convince his council of nobles that his son Edward was the rightful heir to his throne, not his nephew Æthelwold, a Saxon susceptible to alliances with the Danes. And the astonishing upshot of this discovery is that Julius Caesar neither invaded nor conquered Britain in 54 BC.”
Along with the collected letters of Cicero, the memoirs written by Caesar while he was conquering France and other areas of central Europe in the fifth decade of the first century BC is believed by many to be one of the few manuscripts to have survived the period. But there is a very good chance that Caesar’s ‘Commentaries’ did not survive, and that ‘Bellum Gallicum’ (BG), the title it is known as today, was the work of other writers. Historians are wrong to treat it as gospel and to suppose this was the true voice of Caesar. But many do, and therefore they duly accept that he invaded Britain.
The basis for this? That the earliest manuscript of the BG is 9th century, “coinciding with Alfred’s life”; that Caesar “lapses” into first person in the BG; “120 examples of Alfred’s idiosyncratic writing style”; 40 references to Alfred himself (which a forger would naturally introduce into his work); and so on.
But curiously I can’t find any other source for this story. Nor can I find any sign of a Rebecca Huston, associated with National Geographic. Which is more than odd, all by itself.
A glance at Texts and Transmissions reveals that the Bellum Gallicum is transmitted by two families of manuscripts, both with a 9th century exemplar. The first was written at Fleury in the second half of the century, the other at Corbie in the 3rd quarter of the century. The first family contains mainly the BG; the other contains all the commentaries. Neither manuscript is British or associated with Britain, as far as I can see.
As for the other evidence, I must defer to specialists. But I have long since grown wary of such claims. Sifting fernseed seems to be bad for the eyes, in altogether too many cases.
Fascinating to see a claim like this, where there seems no discernible motive. Or is it simply a silly-season invention by a journalist?
UPDATE (28/8/17): After writing this, I dropped an email to Ben Hamilton at the Copenhagen Post, who replied very promptly and helpfully, and made clear that the story is genuine. He gave this link at IMDB for Rebecca Huston. I have since also received some emails from Rebecca Huston. It will be interesting to look further into this one.