That kind of stuff is quite common. you take Liverpool they have two teams "Everton"
which is catholic and "liverpool" which is protestant.and they have their counterparts in Scotland Rangers and Celtic....even in the army if you are protestant and from liverpool then you join a Scottish regiment....i don't really understand it myself , so I may be saying some of it wrong ( I tend to get along very well with people of ethnic minorities myself......coz I treat people how they treat me, If they are nice and polite then I am also, to me that is what defines a person..you can't pick racial origin, but you can choose to be polite..being polite is the cheapest thing..............it costs nothing.you don't need to shout about honour, if you behave honouraby then you get it back.
Sadly in soccer you see stuff like this, people who are tribalists and don't just love the game for it's great skill and artistry and just see it as one army facing another.but true sportsmen see it that way and will cheer for great skill such as in the late george best
Very good point about 'tribalism'_ something that is more deeply embedded in our primal brain than we are willing to admit. The 'us v. them' mentality is rampant in subtle and overt manifestations, right down to the kind of cars 'we' drive vs. the cars driven by other people which has been noted as one cause of road rage.
As an example, if you drive a Chevy and are cut off in traffic by a Mercedes, you are likely to be more upset than if it had been another Chevy.
How does tribalism take hold?
Tribalism is an evolutionary trait that we formed to keep people of like genetic material safe from threats posed by those of dis-similar genetic material. Over the years, we learned how to manipulate it through symbols, stories, and central powerful leaders in order to expand our "tribes" and make them more cohesive and powerful. Examples of this are Nationalism, Religion, Team Sports, and even brand affiliation.