The group was founded back in 1995, when a bunch of friends from the suburbs of Copenhagen got tired of the non-violent mentality of the official supporters. Furthermore, some of the group members were earlier assaulted by rival supporters and were keen on every occasion to settle the score.
In the beginning the relationship between the Fanaticos and some of the other Brøndby hooligan groups was not that good. Mostly because in those days, there was a big rivalry between almost all of the mobs. All of this changed in 1996, when some groups got together and formed an alliance named South Side United, counting firms like Pælene, South Side Brigade and Brøndby Warriors.
In the last years, the Fanaticos are one of the most active groups counting, at this moment, some 20 boys in their early- or mid-twenties, all following the casual style.