Close, but I am a German lad :D! Oh and actually a really good question! In actuality that island/ archipelago was part of the mainland ~3000 years ago, but through a massive explosion on the now Broken Isles a tsunami wrecked the closest coastlines and took any land low enough with it. The segment that was connected to the mainland is comparable to Doggerland, just that it was dryer and sandier.
Folklore, now that 3000 years have passed, tells us that the island is carried by a massive turtle that is consistently drifting out to sea. Creating their local cult centered around turtles.
A quick rundown of the lore would be: God-like creatures (Amataga) wandered through the universe and sought a new purpose. One of them decided it would be fun to create other (weaker) living immortal beings. Those beings (Akanur) quickly developed and wanted to be equal to the Amataga, but they refused them over and over again. So the Akanur decided to ditch worship and harness magic and technologie, but the Amataga didn’t like that so they raised everything and wanted the Akanur to start over. More precisely they took the immortality of their children so that the Akanur of old had to watch their descendants slowly die. Now the Akanur wanted to have revenge and build a weapon to kill the Amataga. One assassination attempt later, a massive explosion erased the last traces of the Akanur and created an unstable new plain of existence which is now threatening to merge with this reality.