Andrew Hocking, 57, of West Sussex, sexually assaulted four girls, aged between six and 12, from 1976 to 1990 in Gloucestershire and Hampshire.
He was found guilty of one count of rape and six indecent assaults following a trial at Lewes Crown Court.
Sussex Police said Hocking showed "no genuine remorse" for his actions.
"Hocking stands out as cold, calculating, predatory and ruthless," said Det Con Chris Smith.
"Despite the strong evidence against him, he put the victims through the ordeal of having to recount their episodes of abuse."
Detectives discovered records of allegations of indecent assaults on a seven-year-old girl at his home in Alveston, Gloucestershire in 1976 and 1977, while they were investigated him over the making of indecent images of children.
Police were contacted by three woman claiming they had been attacked, when they were aged six, seven and 12, by Hocking at his address in Fareham, Hampshire, in the 1980s and 1990, following an appeal for information.
Following a trial, Hocking was convicted of one count of rape and six indecent assaults and cleared of one indecent assault.
The 57-year-old admitted making indecent images of children and possession of extreme pornography at an earlier hearing.
He was ordered to be put on the sex offenders register for life.
A paedophile, branded "calculating and predatory", has been jailed for 15 years for a string of sex attacks on girls as young as six years old.