This, of course, is unhistorical.
The phrase "Invention of the Cross" means the finding of it; the word invention in English does not now translate the Latin "inventio."
The Veneration of the Cross, or Creeping to the Cross, was known in Anglo-Saxon times, but whether as early as Cynewulf's day, seems uncertain.
"Alderman" is the modern form, but it does not mean the same thing.
i.e. of English Christianity.