Dietro di me vs. dietro a me

Question

Are these uses of prepositions interchangeable in the above example, or do they have different emphasis/meanings/uses?

Answer 1

You can use "dietro a" for verbs that indicate movement, like

• andare: go
• correre: run
• camminare: walk

Io cammino dietro a Luigi.

You can use "dietro di" when it precedes a pronoun:

Io corro dietro di te

Remember that "dietro a" is more literary, for example Dante used it:

"Vien dietro a me, e lascia dir le genti" (Purgatory)