Thank you Jim for your reply and exictement in investigating with us
The Donauknie is a bend in the river within the region of Budapest. This used to be a strategic point in the medieval times due to the many river connections to other regions/countries. The English term would be "Danube Bend".
If i were to guess, it is a Oakshot type XII due to the tapered blade form and long fuller.
Personally i don own any reference books but a friend was so kind to show me these sources for the pommel shape. It would date the sword to 1150 up to 1250 (?)