Warren Free, who was allegedly murdered by six teenagers, had previously suffered brain damage when he was the victim of a machete attack, the jury was told on Wednesday (July 1).
Lincoln Crown Court heard that the incident in 2003 occurred in the North Wales town of Colwyn Bay.
Daniel Bishop, for the prosecution, said: “Warren Free was attacked with a machete and received multiple blows to the head.”
Mr Bishop said that since that incident Mr Free had been involved in a number of confrontations.
The jury has previously heard that Mr Free was also attacked in an earlier incident in the same week as he died.
The 42-year-old was walking along Acacia Avenue, Spalding, when a man grabbed hold of him, knocked him to the ground and punched him a number of times.
The prosecution allege that later the same week Mr Free suffered fatal injuries after he confronted a group of teenagers in the early hours of the morning about noise they were making in a park at the rear of his property in Coronation Close, Spalding.
It is alleged that he was kicked, punched and stamped on by the teenagers before a girl struck him over the head several times with a metal pole.
He went home to bed but friends were later unable to rouse him. An ambulance was called and he was airlifted to hospital but passed away within 24 hours from a head injury.
Six teenagers all deny the murder of Warren Free on 29 August 2014. Three of the defendants, including a girl, were 14 at the time while the others were a girl of 15 and a 16-year-old together with Jake Edwards (now 18), of Mill Green Road, Pinchbeck.
Two of the boys, who were 14 and 16 at the time, each deny a charge of perverting the course of justice relating to the disposal of the metal pole in a nearby waterway.
The trial continues.