Dacia

The modern Romanian pronunciation of the word would be DAH-cha.

* /me screams at getting three different dates (105, 106, and 107) from three different normally reliable on-line sources.

/me then thanks Gone Jackal for being smarter than the bunch of them put together. The Second Dacian War lasted from 105 to 107, but the official incorporation of the province took place in 106.

From some indeterminate time in the early middle ages, the Latin name Dacia came to refer to Denmark (while still being used to refer to the Roman province, as well). Nobody seems to be exactly certain when this began, but Dudo certainly refers to "the Dacian tongue" spoken by the northmen. The general consensus among scholars is that this confusion was caused by the fact that Dacia-the-Roman-province was familiar to the mediaeval geographers, while Denmark was not - one imagines them frantically trying to figure out who these strange raiders were, and where they came from. A more correct Latin form of Danmark would be Dania, but this never really caught on.

Runic alphabets were also unfamiliar, and often misidentified as Syriac or Chaldean by mystified scholars of the time.