Jeremy Lowndes, 65, was also ordered to pay 4m pesetas (pounds 20,000) in compensation to his stepson.
In their verdict, the three judges said that on 21 July, 1992, Lowndes got into 'an excited state' owing to a mixture of depression and an excess of alcohol. He got angry with his 68-year-old wife, Carmel, for a reason which was not determined and beat her repeatedly, first with his fists and then with an heavy, unspecified instrument.
The judges, sitting at Cadiz, said they accepted the evidence of Lowndes' stepson, John Wodehouse, that he entered his bedroom and said: 'I think I have killed your mother.' The judges dismissed the defence that Lowndes could not have committed the crime as his clothes bore no blood stains, while the walls of the room where the killing took place where spattered with blood.
According to the verdict, Lowndes killed his wife without his shirt on and then put on the garment.
Under Spanish law a prisoner would be expected to serve only half of the sentence and has Lowndes has been in custody for two years. Lowndes moved to Spain in 1989 after selling off property in England.