Complex sentence: The swords are at the transitional point between the Viking sword and the high medieval knightly sword, most of them with blades of Oakeshott type X. They are also the starting point of the high medieval tradition of (much more varied) blade inscriptions.
Split into simpler sentences: The swords are at the transitional point between the Viking sword and the high medieval knightly sword. Most have blades of Oakeshott type X. They are also the starting point of the (much more varied) high medieval tradition of blade inscriptions.