Factions that aren’t really firm about what they believe, shift positions, but are dead-set in their hatred for one another to the point of dehumanization? In a weird way, such partisan animus for its own sake sounds an awful lot like the ancient rivalry between the Blues and the Greens—the chariot teams turned political parties that played such a prominent role in sixth-century Byzantine political life. As with modern Republicans and Democrats it was never entirely clear what they stood for beyond opposition to one another, but rioting between the two factions ultimately burned half of Constantinople to the ground.
When the Blues and Greens set about burning down their city, they were encouraged by senators who hoped to seize the imperial throne for themselves. They sought to take advantage of the chaos.
Nothing much has changed over the centuries.
– J. D. Tuccille, Mutual Hatred Is All Democrats and Republicans Have to Offer