Domitian ( Titus Flavius Domitianus , 24 October 51 â `` 18 September 96 ) was a Roman Emperor who reigned from 14 September 81 until his death . Titus Flavius Domitianus ( 24 October 51 â `` 18 September 96 ) , commonly known as Domitian , was Roman Emperor from 81 to 96 .