Further to rogerr's excellent answer.
This is one of two staues on the roof of the Vienna State Opera.
The following is from the Opera House's Official Website:~
"Ernst Julius H�hnel
The two representations of riders over the main fa�ade of the loggia were erected in 1876. They were created by Ernst Julius H�hnel and represent two flying horses, illustrating Harmony and the muse of poetry (Erato)."
However,quite which your horseman is you will have to decide.I plump for Harmony.