The First Dwarven King
When humans reached the Mount Golen searching for the Archfey they found the Dwarves who had been abandoned by their Archfey lords. The first Dwarf who would speak to the men called himself Speaker for he was made to speak to others besides Dwarves. The humans asked of the Archfey and when shown there was none they were asked for a leader so they could deal with the Dwarves. Unaware as to how the Dwarves where made or how they understood everything Speaker asked if they could have a day to make him. The humans thought they would elect a King but in truth the Speaker got all the Dwarves together and created the first King of Dwarves.
The myth is almost entirely correct though the humans were far more antagonistic in their demands to find the Archfey, when no Dwarf attacked the leader of the humans thought to make an ally instead of an enemy.
Variations & Mutation
Humans and Dwarves have slightly different version though the human focused story has spread further which happens to play down the automaton nature of the first dwarves. Instead Dwarven patois is played heavily almost to comical standards.
This myth was all but ignored till a few adventurous Dwarves brought back Bards and playwrights to teach other Dwarves. There the bards learned of how Dwarves were made and the truth about the first contact with humanity. They changed the story slightly to better appeal to other races but kept most of the story intact and created several songs and plays about the first Dwarven King and how he was made. A modern retelling has risen in popularity has risen among humans that turns the story into a comedy of errors called The Rise of the Mountain King.
The Rise of the Mountain King