Complex sentence: At the end of 12th century one of the most important literary works of the times, Nibelungenlied, emerged which was created by an unknown minnesang poet most probably in the territories of Austria.
Split into simpler sentences: At the end of 12th century one of the most important literary works of the times, Nibelungenlied, emerged. It was created by an unknown minnesang poet most probably in the territories of Austria.