"Cryptocurrencies have a big future," Bannon told CNBC on Friday. "They could be a very important part going forward, particularly in this global populist revolt."
As an owner of bitcoin, Bannon said he had "enough foresight, enough courage to buy as it went all the way down."
Bannon has generally towed the Trump line on hot-button issues since his departure as White House chief strategist in August 2017, not even a year after the presidential inauguration.
Last month, after Facebook's June announcement of its Libra digital currency effort, Trump tweeted, "I am not a fan of Bitcoin and other Cryptocurrencies, which are not money, and whose value is highly volatile and based on thin air." He added, "Unregulated Crypto Assets can facilitate unlawful behavior."
Bannon said that governments, central banks and the banking industry want to "stay with fiat currency" so it's no surprise that they "get in there and regulate crypto." Fiat currency is legal money backed by governments.
Unlike the decentralized nature of bitcoin, Libra will be pegged to a basket of government-backed money.
As part of his July cryptocurrency diatribe — and ahead of contentious Libra hearings on Capitol Hill — Trump said Facebook's Libra "will have little standing or dependability," adding that if the social media giant wants to become a bank it should seek a banking charter.
Bannon sees Libra a bit differently, acting in practice as more of a competitor to mobile payment systems that already exist than traditional cryptos like bitcoin. The Facebook effort is "principally against" some of the major Chinese companies offering their own payment systems such as Alipay that was created by Alibaba and WeChat Pay from Tencent.
"I think what people need to confront now and people start looking at, is how the Chinese and Third World countries in sub-Saharan Africa, in South Asia and I think potentially in South America, are starting to put these payment systems in that are going to kind of give them, try to give them, global dominance and be able to get off the reserve currency of the dollar," Bannon said.