Local authorities tried to ban the rally that has been held every year for over a decade, and which the government has slammed as "shameful".
But organisers obtained a court order allowing them to proceed.
Dozens of members of far-right groups from across Europe also took part.
"We object to being called anti-Semites, neo-Nazis, or fascists. We are simply nationalists," rally leader Zvezdomir Andronov told AFP.
Swede Robert Eklund from the Nordic Resistance Movement said that he was in Bulgaria "to fight a common enemy -- multiculturalism, globalisation and the EU", adding he wanted "to stop non-European immigration."
The black-clad protesters marched through downtown Sofia for over two hours, lighting torches and chanting the name of Hristo Lukov, a Bulgarian general known for supporting Nazi Germany during World War II and for his anti-Semitic views.
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![Polling clerks counted votes at a polling station after completing the voting process of the general election in Abuja, Nigeria, on February 25, 2023. [Getty Images]](data:image/svg+xml;charset=utf8,%3Csvg%20xmlns%3D'http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg'%20width%3D'300'%20height%3D'172'%20data-ring-placeholder%3D'1'%3E%3C%2Fsvg%3E "Polling clerks counted votes at a polling station after completing the voting process of the general election in Abuja, Nigeria, on February 25, 2023. [Getty Images]")
