PHILADELPHIA -- There are two working theories as to why a 1,000-pound bronze statue of a Viking was toppled off its base and into the nearby Schuylkill River early Tuesday morning in the popular Fairmount Park section of Philadelphia.

The first -- the one being pursued by authorities -- is that it was done by anarchists to counter white supremacists' claims to the Icelandic voyager. Naturally.

The second is it was the work of Philadelphia Eagles fans to (disturbingly) mark the beginning of Vikings week. Philadelphia plays host to Minnesota on Sunday (4:25 ET, Fox).

However off target, the latter is perhaps the most widely accepted explanation in the public sphere, which says plenty on its own about how far this rivalry has come in a short amount of time.

It's an unlikely squabble between two fan bases that represent teams in distant regions and different divisions. And frankly, it's hard to picture placid Minnesotans getting into a dust-up with anybody. But a very unique set of circumstances over the course of a few weeks last winter stoked the embers and led to a beer-tossing, name-calling, service-revoking mini-feud that makes Sunday's rematch of the NFC title game in South Philly all the more intriguing.

It all started early on Sunday, Jan. 21, just a stone's throw from where the statue of explorer Thorfinn Karlsefni took a tumble into the river and, actually, losing its head along the way. A group of Vikings fans made a pit stop before heading to Lincoln Financial Field for the NFC Championship game, gathering on the Philadelphia Museum of Art steps -- sacred ground to locals -- to perform a massive "Skol" chant. The nearby "Rocky" statue was even dressed in purple and gold attire.

The images spread like wildfire on social media and throughout the tailgating scene around the stadium, which already was in full swing hours before kickoff.

"I kept having that image of them doing the 'Skol' chant shoved into my face: 'Did you see what they did on the Art Museum steps? Did you freakin’ see this?'" remembers Eric Emanuele, better known as EROCK, a longtime season-ticket holder, podcast host for NBC Sports Philadelphia and recognized as a leader in Eagles Nation. "I think the reason why the Vikings fans had such a miserable time at the game is because the people at the game were acutely aware of where they just came from and what they just did on the Art Museum steps and felt disrespected.”

This, mixed with a high-stakes game and drinking -- lots and lots of drinking -- led to a volatile scene in the parking lot. We're not talking about the Thunderdome here -- most fans behaved themselves and offered a ribbing at most to their purple-clad visitors as they passed by -- but there is video of Vikings fans having beers thrown at them as they walked toward the stadium, and others of Eagles fans being rather aggressive in their heckling. And, oh yeah, a police horse got punched (allegedly).

Then-Minnesota quarterback Case Keenum said that when it came to the treatment of his family at the game, there were "some situations that were not good," and he had some friends there "to intercede." On their way out, the Vikings bus was pelted by beer cans.

Some Minnesotans who had made the trip were shocked by their experience and vowed never to never set foot on Philadelphia turf again.

“You’ve got to understand. If you’re making that flight out from Minnesota, you’re talking about upper-middle class to upper class, disposable income, because those tickets weren’t cheap, that flight wasn’t cheap, and I guarantee you it was hard to find a hotel room and you were paying premium to go get there," Emanuele said. "So you’re talking about a bunch of individuals -- Levi's jeans-wearing, I-want-to-talk-to-your-manager, haircut-having soccer moms that are not used to a 19-year-old kid who has been drinking in the parking lot all day going up to them and screaming, ‘Go Birds!’ You just have a clash of cultures both from Philadelphia and Minnesota, and then, I feel, like an age or a socioeconomic bracket, as well.

"When the Vikings fans got there, having done what they’d done on the Art Museum steps, they were not expecting the kind of cultural backlash from a fan base that was absolutely pissed off, ravenous and ready to watch their team go to the Super Bowl, let alone the fact that alcohol was involved -- heavily.”

The Eagles crushed the Vikings 38-7 to advance to Super Bowl LII, which, as fate would have it, was held in Minneapolis. Bitter about the loss and soured by tales fellow Vikings fans brought back from Philadelphia, the region exacted revenge -- in a very Midwest sort of way.

The term is "Minnesota nice," which in this instance is code for passive-aggressive behavior. Residents were outwardly courteous, as always, but found ways to poke the bear.

There were stories of locals canceling Airbnb's on Eagles fans and plots hatched in which locals signed up as Uber drivers just so they could drop Philadelphians off at the wrong place. A sign outside one bar/restaurant read, "Eagles fans: Stop in and have a FREE BEER ... thrown at you."

"I just know that anywhere that I hear of, nobody wants to help them," Chad Waldon, identified as a manager at one of the top eateries in Minneapolis, Butcher & the Boar, said of Eagles fans and players. "I think we're far more civilized than that [regarding reports of violent celebrations from Eagles fans], but we'll do it in our own passive-aggressive Minnesota way; we just won't let them eat dinner in our restaurants."

Eagles safety Chris Maragos said it took him a day and a half to find a restaurant that would accommodate him and his teammates.

“Usually, a lot of times you can’t get in a place and then maybe I can explain to them that my teammates and I are coming in and maybe that’ll help, but no dice there for a while. It was pretty funny,” Maragos said. “We had a hard time. We got in, though.”

The Eagles got the last laugh by securing their first Super Bowl title on Minnesota soil.

The meeting between the Eagles (2-2) and Vikings (1-2-1) is different this time around. Both are trying to shake off early loses and regain their footing as NFC elites. Eagles players are well aware they are not only facing a desperate Vikings team, but one with revenge on their minds.

“There’s no doubt there will be some added motivation this week for the Minnesota Vikings," Eagles center Jason Kelce said. "You’d be foolish not to think that."

The memories are fresh, both for the respective teams and fan bases. It should make for an intriguing scene come Sunday.