Simon Hailes, 40, from Kidderminster, died of serious head injuries at Pinderfields Hospital, in Wakefield, on Saturday, September 25, a week after being injured.
Paramedics were called to Pontefract at around 4.50am on Saturday, September 18, after receiving reports a man had suffered head injuries.
A spokesman for West Yorkshire Police said: "Detectives are continuing their enquiries to establish the full circumstances surrounding the death of Mr Hailes.
"Two people arrested on suspicion of assault in connection with the incident were bailed pending further enquiries."
Anyone with information about the incident is asked to contact West Yorkshire Police quoting reference 285 of September 18.
Alternatively, call Crimestoppers anonymously on 0800 555 111.