Saturday's protest was organized by the so-called "sardines", a youth movement that sprang up spontaneously a month ago in Bologna and which has since added followers of all ages all pitted against Salvini, reports Efe news.
The protesters waved signs with drawings of sardines and such slogans as "Rome will not surrender" and "No to hate", while singing partisan songs like "Bella Ciao" and the Hymn of Mameli, the national anthem of Italy.
Their intention was to send a message to parties of the far right that they spread hate and racism against freedom, tolerance and equality.
The protests first erupted on November 14 in Bologna and the demonstrators adopted that name to show they can pack plazas like sardines in a tin can.
Since then the trend has spread to a number of cities around Italy, and this Saturday established itself in the capital to keep gaining support and awakening social conscience to stop the far right.
The unprecedented sardines movement was founded in Bologna by four young men who have built support via social media.
One of them is Matteo Santori, who said this Saturday that "when the beast of populism launches an electoral campaign, we must know there will be tough times ahead".
Santori called for the immediate elimination of the decrees introduced by Salvini when he was Interior Minister, which in turn led to tougher policies against illegal immigration while creating division and racism.
"We want laws that see diversity as riches," he added.
( With inputs from IANS )