Why was the cross of lothair created?

It was made as an important monument of imperial ideology.

The cross: around the year 1000

The basis: around 1450

Art periode cross: Late Ottonian art that was evolving into Romanesque art

Important: outstanding example of medieval goldsmith's work (most items of that kind (there were not many to begin with) did not survive until today).

Also important as it shows incorporates a roman cameo of Augustus and thus Lothar shows clearly he is "Kaiser" (ceasar)