Suva High Court judge Nazhat Shameem handed down the sentence after Seniloli was convicted of taking an illegal oath to commit a capital offence, when he was sworn in as usurper president during the coup.
Radio Legend reports that four other men convicted for purporting to become ministers in Speight's rebel administration have been sentenced to various terms according to the extent of their participation in the coup events.
They are the deputy Speaker of parliament Vakalalabure who has been jailed for six years, Viliame Volavola and Peceli Rinakama 3 years each, and Viliame Savu, who had already served a sentence for misprision of treason, has been given 12 months.
In mitigation earlier today, all the defence lawyers asked for non-custodial sentences, saying prison terms would have devastating effects on their clients and their families.
The five convicts also apologised to the nation for their actions during the coup and asked for forgiveness.
But Justice Shameem said the offences were serious, had caused untold suffering and a suspended sentence was not appropriate.
She said Seniloli had betrayed the then president Ratu Sir Kamisese Mara and and used his chiefly status bto give credibility to Speight's regime.
She also took into account the damage done during the coup, the burning and
looting and the thousands of people who were affected by the actions of the five.
Justice Shameem had originally set higher sentences but reduced the terms to the ones she actually imposed after taking into account their previous service in government and the military.
The men will be spending the weekend in prison, with any appeals and bail applications not due till next week.