Danes are a race of people on Earth.
They are known for having conquered England. They are also known for having built the Daventry (at least the parallel one of the Other World). The area is sometimes locally called Daintry by its ancient name, pronounced "Danetree" (or Dane-tree).
There may be some kind of connection between the Kingdom of Daventry and those in England, but how so is not clearly known. However, the name Daventry or its ancient spelling, is based on the name of its founders. This may suggest that the Kingdom of Daventry may also have been founded by the Danes.
When the Ogre smelled Rosella in his closet, he was about to call her English, which suggests she is ancestral related to the English and/or the Danes. The people of Daventry speak a dialect of English known as the common tongue.