Incredible sonar images show the 100-year-old wreck to be mostly intact, and the find has led to the resurfacing of nautical folklore. Experts say the wreckage may be the infamous UB-85, which, legend has it, was attacked by a sea beast during the war.
According to the old tale, the U-boat commander -- Capt. Gunther Krech -- said the submarine had been cruising on the surface of the water to recharge its batteries when a "strange beast" rose from the sea with "large eyes, set in a horny sort of skull." Krech said the animal had a small head, but with "teeth that could be seen glistening in the moonlight," according to a statement from Scottish Energy News
Scottish Power crews discovered the wreckage when surveying the seabed to lay a new power cable.
The story goes that the sheer size of the beast was so immense that it forced the U-boat to list and the crew began shooting at the monster until it dropped back into the sea. The captain said, however, that during the course of the fight the forward deck plating had been so badly damaged that it could no longer submerge.
The British military had a slightly different take on the incident. Official reports suggested that when the UB-85 surfaced on April 30, 1918, it was spotted and destroyed by a British patrol boat -- HMS Coreopsis -- not by a mysterious sea monster.
The history of U-boats
Laura Clouting, a historian at Imperial War Museums, told CNN these types of submarines were deployed to disrupt trade by targeting the vessels bringing imports into Britain.
"These submarine attacks were very effective and destroyed millions of tons of goods into Britain," she said. "It was a long-term strategy."
Clouting said given that Britain is an island, it was crucial for it to import from all over the world to feed its people. She said the U-boat strategy was controversial, leaving many of Britain's allies angry.
"America was furious with the U-boats that indiscriminately targeted passenger liners rather than a legitimate military target."
Philip Robertson from Historic Scotland told CNN that eventually, Britain's Royal Navy introduced convoys to guard and protect vessels that were importing goods. This target made it more difficult for U-boats to identify what liners were bringing in goods.
"That was very influential and resulted in a rapid decrease in German attacks on allied shipping."
Mystery still unanswered
While researchers can't confirm the wreck discovered off Scotland's coast is the mysterious UB-85, Innes McCartney -- a historian and nautical archaeologist -- said they may be one step closer to concluding the mystery of the ship.
McCartney confirmed it was a UBIII-Class submarine, but there are two which it could be -- the more famous UB-85 or its sister boat UB-82.
"While I can conclude that this wreck is likely to be one or the other, they would be practically impossible to tell apart, aside from the numbers painted on them in service, now obviously long gone," he said in the Scottish Energy News statement.
"Unless a diver can find a shipyard stamp, we cannot say definitively but yes, we're certainly closer to solving the so-called mystery of UB-85 and the reason behind its sinking -- whether common mechanical failure or something that is less easily explained."
But Gary Campbell, the keeper of the Official Sightings Register of the Loch Ness Monster, believes "it is entirely feasible that some large sea creature disabled the submarine," and "the area of sea where the attack took place has a history of sea monster sightings."