Former huntsmaster John Norrish, 68, took advantage of the 33-year-old married mother when he offered to give her a lift home in the early hours of the morning.
Norrish, who has been married for 46 years and has two children, claimed she had already removed her knickers and lifted up her ball gown once they were in the vehicle.
But the victim, who was a stranger, denied his claims and said she had told him she did not want to have sex.
She told the court that she may have passed out in his car after downing 20 alcoholic drinks that night at the annual Tiverton Staghounds hunt ball last July at Chawleigh, Devon.
Exeter crown court heard Norrish raped her in the front seat of his 4×4 at around 2.30am.
A jury took more than eleven hours of deliberations before finding Norrish, 68, guilty of rape by a majority of ten to two.
The trial judge, Mr Justice Field, said it was a ‘grave abuse of a vulnerable woman’, adding that the ‘effect of what you did will endure for her for years’.
After the case, the victim told how she had been ‘violated in the most horrendous way’.
She said: ‘I would like to say that this has been the most difficult ten months of my life.
‘A community has been divided and I would like to think that we can now put this behind us and rebuild our lives.
‘John Norrish was seen as an upstanding member of the community and he abused that trust.
‘This result means that no-one else will be subjected to this type of abuse from him.’
There were gasps and tears in the packed public gallery from friends of Norrish who had attended the court every day for his trial.
He had his head bowed as the judge told him: ‘It was in the early hours of July 2 last year when you invited the victim to take a lift home with you. She was drunk.
‘I have no doubt that you appreciated that. Instead of simply giving her a lift home as you should have done, you took advantage of her as she sat in the front passenger seat of your car.
‘She did not consent to your advances, early on she told she did not want to.
‘You did not reasonably believe that she was consenting and proceeded to have sexual intercourse. This was a grave abuse of a vulnerable woman.’
The judge said the victim was ‘too drunk to exercise a free choice to events’.
Norrish remained impassive as the sentence of four years was passed, of which he will serve half behind bars before he is considered for released on licence.
His victim was said to be ‘beside herself with relief’ at the jury verdict and thanked her husband, friends and the police for their ‘support and professionalism’.
She said that after the rape she ran from his car and spotting a car’s lights in the field used for parking – it was a car carrying her husband who had gone to fetch it to give her a lift home.
She said she was ‘hysterical’ and her husband wanted to track down Norrish who drove off with her shoes, knickers and handbag in the footwell of his vehicle.
People working at the ball said they saw the woman after the alleged attack and she appeared calm and was only concerned about a bottle of wine which had been stored in a fridge at the bar.
Det Con Paul Feeney said: ‘She is beside herself with relief at the jury’s decision and now wants to get her head around it.’
Norrish, who has no previous convictions, has a caution for an assault during a hunt altercation.
His lawyer Robert Linford told the judge that his client had led an outdoor lifestyle all his life and a custodial sentence will be hard for him to bear.
Norrish, who is now retired from is job as huntsman with the Tiverton Staghounds, is still married.
He will be placed on the Sex Offenders’ register for life.
Norrish was described by one of the people serving behind the fully stocked bar as ‘the star of the show’ that night.
It was said he stood proudly at the entrance to the Cobley Farm event wearing his red hunting jacket, collecting tickets off the 300-400 people who were attending the Tiverton Staghounds ball last July.
Norrish, who has two grown-up sons, was a big part of the West Country hunting scene.
During his lengthy career, which dated back to the 1980s, he had been associated with the Devon and Somerset Staghounds, the south Devon foxhounds, the Minehead harriers in Somerset and latterly the Tiverton Staghounds.
He lived at the kennels where he looked after the hounds that took part in the hunting over Exmoor.