District Judge Steven Taylor ordered Nichols to serve the life term on each of 161 counts of first-degree murder and that the sentences run consecutively.
Nichols had already been sentenced to life without parole in 1998 on federal bombing charges; Monday's sentence was on the state murder counts. Nichols was spared the death penalty on the state counts when jurors could not agree on a sentence.
The sentence is more symbolic than anything, says CBSNews.com Legal Analyst Andrew Cohen, especially since the Oklahoma jury didn't recommend a death sentence for Nichols. He'll either have to serve out the rest of his days in state prison in Oklahoma, the scene of his crime, or in Colorado, where he already had begun to serve his federal sentence.
The chief prosecutor, Oklahoma County District Attorney Wes Lane, has said he expects Nichols to be returned to federal custody once he is sentenced and the deadline for filing an appeal expires.
A date for his return to federal prison has not been set.
Nichols, 49, never testified during his state and federal trials and said nothing after he was convicted in federal court. But he submitted a lengthy written statement Monday in which he asked for forgiveness and offered to anyone his help in the healing process.
Nichols prayed "for everyone to acknowledge God," and to make God first in their life, the statement read.
But Taylor called Nichols a terrorist and said the redemption and atonement he seeks is only the beginning.
Nichols received 10 years and a $5,000 fine for a conspiracy count; 35 years and a $25,000 fine for first-degree arson and was ordered to pay $5 million in restitution and $10,000 per count to a victims compensation fund, as well as legal fees.
Nichols' federal involuntary manslaughter and conspiracy convictions were for the deaths of eight federal law enforcement officers who were among the 168 victims killed during the April 19, 1995, bombing of the Alfred P. Murrah Federal Building. Jurors at his federal trial also deadlocked on whether to sentence Nichols to death.
The state charges were for the other 160 victims and one victim's fetus. Jurors could not consider a death sentence on the count involving the fetus and sentenced Nichols to life without the possibility of parole for that count.
Nichols now has 10 days to appeal his conviction and sentence, but Nichols' defense attorneys have urged him not to appeal.
Lead defense attorney Brian Hermanson said a successful appeal that invalidated the conviction and sentence could result in a second state trial and another attempt to secure a death penalty.