He was convicted of defying a subpoena to testify before the congressional panel that investigated the January 6, 2021 attack on the US Capitol by Trump supporters.
Bannon, 70, spoke defiantly as he showed up at a federal prison in Connecticut.
“I’m proud of going to prison today,” Bannon said, “if it’s what it takes to stand up to Joe Biden.”
Bannon and others argue that legal proceedings stemming from the January 6 insurrection against the seat of US democracy amount to political persecution designed to thwart Trump’s bid for re-election in November.
A cluster of people waving “Trump 2024” flags greeted Bannon outside the prison, as did Marjorie Taylor Greene, a fiercely pro-Trump lawmaker from Georgia who is one of the new faces of the Republican Party tightly controlled by the former president.
One of the masterminds behind Trump’s successful 2016 presidential campaign, Bannon was sentenced to four months in prison in October 2022 but remained free until now while appealing his conviction.
A federal appeals court upheld the conviction in May, and District Judge Carl Nichols, a Trump appointee, revoked Bannon’s bail at a court hearing early this month, ordering him to report to prison by July 1.
Bannon served in the White House as chief strategist for the first seven months of Trump’s term, leaving reportedly due to conflicts with other top staffers.
In 2020, he was charged with wire fraud and money laundering for taking for personal use millions of dollars contributed by donors for the construction of a border wall with Mexico.
While others were found guilty in the scheme, Trump issued a blanket pardon to Bannon before leaving office in January 2021, leading to the dismissal of the charges against him.