Taylor James Johnatakis was convicted in November on seven charges, including obstruction of an official proceeding and assaulting police officers.
Johnatakis led rioters in attacking the police line outside the Capitol, according to federal prosecutors.
"Specifically, using his megaphone, Johnatakis directed rioters to move up to the police line and yelled at the rioters to 'pack it in! pack it in!'" a press release states. "Johnatakis then instructed the crowd through the megaphone that they were going to push the bike racks 'one foot' at a time and counted, 'one, two, three, GO!!'"
At least one officer was injured in the fray, prosecutors said.
During his trial, Johnatakis represented himself, frustrating Judge Royce Lamberth with his erratic behavior. He argued his case by claiming to be a "sovereign citizen," The Associated Press reported, which the judge called "gobbledygook."
Johnatakis also asked the judge questions during his sentencing, including "Does the record reflect that I repent in my sins?" -- to which Lamberth replied he was not taking questions, the AP reported.
In a letter after Wednesday's hearing, Lamberth said every decision on how to sentence Jan. 6 rioters "aims to discourage these defendants from future violence, dissuade others from taking inspiration from the Capitol riot, and express the community's moral disapproval of this conduct."
He hit back at the idea that Johnatakis was simply exercising his freedom of speech, saying his actions were "neither First Amendment-protected activity nor civil disobedience."