Actually, Caesar was very self-interested and got very rich from his campaign in Gaul. Plutarch estimated that Caesar brought back (and sold) a million slaves.
The strong minority base that has been artificially inflated to advance the personal interests of the leadership has linear roots dating back to the XX century rhetoric promoters and activists. In Europe there's the militant and militia groups of Gladio and the likes that thrived in illegal affairs and that have persisted and were integrated into power following 90s (case in point in Italy Berlusconi basically legalizing the MSI, AN, FdI and Lega by using his privately owned televisions and media, to acquire an election victory).
In reality "fascist" is a qualifier to frighten white people voting for a right-wing government. Trump base by the way is not fascist, it's the evangelical bible belt. Which is crumbling at the moment, by the way.