The term "Loch Ness Monster" was created in 1933, in the wake of a number of sightings of strange creatures seen in the waters of Loch Ness, Scotland - and, on occasion, even briefly on the land. Although Loch Ness has a longstanding tradition of supernatural entities in its midst (they were known as Kelpies and Water-Horses, there's no doubt that the earliest report is that of St. Columba, which actually occurred in the River Ness, which flows from the northern end of the legendary loch. The story can be found in Book II, Chapter XXVII of St. Adamnán’s Vita Columbae.
To say that it’s quite a tale is, at the very least, an understatement. Born in the town of Raphoe, Ireland in 624 AD, St. Adamnán spent much of his life on the Scottish island of Iona where he served as an abbot, spreading the word of the Christian God and moving in very influential and power-filled circles. He could count amongst his friends King Aldfrith of Northumbria and Fínsnechta Fledach mac Dúnchada, the High King of Ireland. And he, St. Adamnán, made a notable contribution to the world of a certain, famous lake-monster.
St. Adamnán’s Vita Columbae (in English, Life of Columba) is a fascinating Gaelic chronicle of the life of St. Columba. He was a 6th century abbot, also of Ireland, who spent much of his life trying to convert the Iron Age Picts to Christianity, and who, like Adamnán, was an abbot of Iona. In 563, Columba sailed to Scotland, and two years later happened to visit Loch Ness – while traveling with a number of comrades to meet with King Brude of the Picts. It turned out to be an amazing and notable experience, as Vita Columbae most assuredly demonstrates. Adamnán recorded the following:
"…when the blessed man was staying for some days in the province of the Picts, he found it necessary to cross the river Ness; and, when he came to the bank thereof, he sees some of the inhabitants burying a poor unfortunate little fellow, whom, as those who were burying him themselves reported, some water monster had a little before snatched at as he was swimming, and bitten with a most savage bite, and whose hapless corpse some men who came in a boat to give assistance, though too late, caught hold of by putting out hooks.”
After that, it was pretty much silence - and for almost 1,000 years. Indeed, the next report of a Nessie dates from the early 16th century: 1520. It should be stressed this does not mean there was a complete absence of encounters in the intervening years. It suggests that, possibly, no-one chose to speak about what they may have seen. Or, more likely, if the details of sightings were passed down orally, and among close-knit communities close to the loch, they may have become forgotten and lost to the fog of time.
As for the 1520 case, the details came from a man named David Murray Rose, a historian who was particularly active from the late 1800s to the 1930s. It was in 1933, when Nessie mania was in full-swing, that Rose contacted the Scotsman newspaper about his knowledge of an early episode of the Nessie variety. In a letter of October 20, 1933, Rose stated that post-St. Columba, the next reference to the presence of strange creatures in Loch Ness harked back to 1520.
Rose cited as his source an old manuscript (unnamed, unfortunately, and which is a big problem when it comes to the matter of validation) that was filled with tales of all-manner of strange and legendary creatures, such as fire-breathing dragons and ghostly hell-hounds. According to Rose’s research, the book in question described how one Fraser of Glenvackie slaughtered just such a dragon – in fact, what was said to be the very last Scottish dragon – but not before the beast managed to scorch much of the landscape. Interestingly, Rose said that the author of the book made a comment to the effect that although the dragon was slain, the creature of Loch Ness (which was then "lately seen") lived on. "Lately" being 1520.
While Rose’s account is unfortunately brief, and lacking in actual documentation, it does demonstrate - to a degree, at least - that more than five hundred years ago there existed a tradition of mysterious animals in Loch Ness and long before the terms, "Nessie" and "Loch Ness Monster," were coined.