Charged with affray are James O'Brien, 21 and from Rylagh Road; Mark Donnelly, 21 and from Greencastle Road; Aaron Davis, 19 and from Beattie Villas; and Aaron Bradley, 18 and from Waterworks Road - all in Omagh - and a 17-year-old youth, who cannot be named for legal reasons.
Aaron Bradley is also charged with the actual bodily harm of Liam Williams, a friend of Jason McGovern.
A police detective constable told Omagh Magistrates' Court on Saturday that he believed he could connect all the defendants with the charges.
Jason McGovern had gone out in Omagh last Sunday night. The court heard of two attacks on him in the early hours of New Year's Eve, Monday 31 December.
He was assaulted at the Terrace Bar on John Street after an altercation with a large group of people at around 2am.
The court heard Mr McGovern was then punched in the face several times, dragged to the ground and assaulted while on the ground.
He then went to the nearby Kelvin Road, close to the Weigh Inn bar, where he was approached again.
The victim was punched in the face and fell backwards onto the ground.
After falling unconscious following the second attack, the 19-year-old was helped into a taxi and taken to his friend's house at Emyvale, Co Monaghan.
He was found dead in bed later that day at around noon.
The court was told that there was a strong possibility the fatal head injury was the result of Mr McGovern falling to the ground due to the second attack.
All five defendants have been bailed on strict conditions and are due to return to court on 22 January.