The "magic" symbolized is that of genuine poetry; but the magician, or "mage," is an historical person; and the special feat imputed to him was recorded of other magicians in the Middle Ages, if not of himself.
"Johannes Teutonicus, a canon of Halberstadt in Germany, after he had performed a number of prestigious feats almost incredible, was transported by the Devil in the likeness of a black horse, and was both seen and heard upon one and the same Christmas day to say Mass in Halberstadt, in Mayntz, and in Cologne" ("Heywood's Hierarchy," bk. iv., p. 253).
The "prestigious feat" of causing flowers to appear in winter was a common one. "In the year 876, the Emperor Lewis then reigning, there was one Zedechias, by religion a Jew, by profession a physician, but indeed a magician. In the midst of winter, in the Emperor's palace, he suddenly caused a most pleasant and delightful garden to appear, with all sorts of trees, plants, herbs, and flowers, together with the singing of all sorts of birds, to be seen and heard." (Delrio, "Disquisitio Magicæ," bk. i., chap, iv., and elsewhere; and many other authorities.)
"Wine of Cyprus." The quotation heading the poem qualifies it as 'wine for the superiors in age and station.'
Such as Wordsworth assumed to have been in use with Shakespeare.