Paul Musto, of Jeffrey Lane, Doncaster, was finally brought to justice more than 40 years after carrying out his distressing crimes against the three children.
The 63-year-old defendant, who used to run the Ship Inn in Lancaster, was convicted of one charge of rape, one charge of attempted rape and 12 charges of indecent assault against the schoolgirls after a trial that lasted just over a week.
Some of the disturbing offences took place at an address in Weeton, near Preston.
Judge Stuart Baker, sitting at Preston Crown Court, imposed a 12 month extended licence to run after Musto is released from his prison term.
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He will be in his 70s by the time he is given parole.
The licence will run alongside an indefinite sexual harm prevention order against the disgraced former soldier, who is believed to have served in the Gloucestershire Regiment - nicknamed the Glosters.
The publican, who used to run the social club in Thornton-Cleveleys after leaving the army, was convicted by jurors after harrowing recounts of the offences were given in court by his victims.
His denials meant all three, who are now grown women, had to go through the trauma of giving evidence.
One of the victims, who cannot be identified for legal reasons, was allowed to give her evidence from behind a screen.
She told jurors: “By the time I had realised it wasn’t right, it seemed a bit like I should have said something sooner to be believed.
“Then obviously there’s the consequences of other people finding out or judging me, or actions people might have taken as a result of what had happened.
The court order will prevent him having any contact with children aged under 16s when he is released.