Paul Ritchie, 34, targeted prominent politicians including former Home Secretary Amber Rudd, SNP leader Ian Blackford, and ex-Lib Dem leader Jo Swinson during Britain’s withdrawal from the EU in 2019.
He sent emails to Chuka Umuna and Lib Dem leader Sir Ed Davey saying “we will kill you and your entire family”.
He told Plaid Cymru leader Adam Price that he “deserve(s) to get shot in the face” and asked Ms Swinson if she was “trying to get shot”.
Ritchie also sent gun symbols to Mr Blackford saying “I hope you die”, and told former attorney general Dominic Grieve: “If you stop Brexit we will decapitate you.
In messages to Mr Corbyn, Ritchie called the former Labour leader a “terrorist”, suggested he should be “hung for treason”, and added: “Murdering you would be fully justified”.
Ritchie, who now lives in a village on the Scottish borders, made repeated references in the messages to murdered MP Jo Cox, and told Mr Bercow: “If you thwart Brexit we will decapitate you.”
Despite the tirade of vitriol aimed at MPs perceived to be blocking Brexit, Ritchie has said openly he voted Remain in the 2016 referendum.
In an email to Ms Swinson, he revealed he had “personally voted Remain” but told her: “I wouldn’t even spit on you if you were burning to death - you have not accepted that Brexit won the vote.”
At Southwark crown court he admitted 28 counts of sending an electronic communication with intent to cause distress and anxiety, between March and August 2019.
Judge Adam Hiddleston sentenced him to 12 months in prison for the “vile” abuse, saying: “Those who received the emails will no doubt have been left in great fear for their personal safety and for the safety of their loved ones.
“It’s clear the sentiments expressed by you in those emails went considerably beyond what could be described as legitimate expressions of your political views.”
The court heard Ritchie has also admitted a string of similar offences in Scotland.
He used personal and work email accounts to send the abusive messages, at a time when the Brexit debate was raging across the country and former Prime Minister Theresa May tried and failed to get her deal with the EU approved by Parliament.
Mr Price said he was “unsettled, upset, and concerned for his personal safety” after receiving a threatening email from Ritchie as he had dinner with his family, shortly appearing on the Andrew Marr show to discuss Brexit.
Sir Lindsay Hoyle, who succeeded Mr Bercow as Speaker of the House, told the court he believes “democracy itself is at risk if as a result of threats and fear, MPs consider not standing for election, reduce interaction with constituents, and change the way they debate and vote in the House.”
He said a recent survey of MPs showed many do not feel safe enough to attend events alone and have cut back on public meetings.
An aide to Sir Ed Davey told the court she now fears opening packages as a result of Ritchie’s emails, adding that she wants Ritchie to understand “the MPs he writes to in the vast majority of cases won’t see the horrible emails and letters, but junior staffers like herself will bear the brunt of the vitriol”.
The court heard Ritchie is currently undergoing psychiatric treatment, and had been suffering depression as well as drinking heavily and taking drugs at the time of the offences.
The judge said Ritchie “harboured deep-seated animosity to those who held opposing views to your own”.
“It’s clear that while intoxicated you allowed your anger to spill over into extreme abuse”, he added.
“These were very serious threats indeed, issued to those who were doing the public duty that they were elected to do.”