I just want to preface this post by stating that Russia isn’t
evil, as stated in his volume 3 character note. Instead, he’s described as “naturally
scary.”

On the other hand,
the spirits, ghosts, and entities that follow Russia may, in fact, be evil.

Is Russia Cursed?: 

Yes.

There are several sources that describe and/ or hint at his curse,
his cursing ability, and the cursed beings that follow him.

1)  The
Russo-Japanese war. The Russian Orthodox Church was allegedly able to curse
Japan.

Russia’s also able to curse Japan after the fact, once
causing the latter to develop a stomach ache.

It’s no wonder that Japan is so opposed to Germany forming
an alliance with Russia during WW2. Notice the supernatural-esque words that Japan
uses to describe Russia: 

“A monster created by fallout from nuclear tests” [x].

2)  To get his revenge on America, England intends
to have him sit on the infamous Busby Chair, a chair that’s rumoured to kill
all those who sit on it.

Instead, Russia sits on the
chair, only to cause it to explode. Something about his aura appears to be too
overwhelming for the chair to handle.

3)   After the failed Busby Chair incident, England
decides to summon a being to “crush America.” Russia appears instead.

There are two reasons why I believe Russia may have appeared in the circle. One, Russia fits the description of what England wanted to summon; he’s large, mentally twisted in that he has a warped sense of reality [x], and as the USSR would have been strong enough to crush America. Two, just the fact that Russia’s cursed.

Of critical importance is that not only does Russia admit to
having a grudge on England – likely stemming from their relations during England’s
Splendid Isolation period – but England also retaliates by claiming that the
two settle their grudge with a magic duel. No such duel occurs, but it’s the
fact that Russia’s capable of using [dark] magic that I want to place stress
on.

4)   The remaining seven G8 countries mistake Canada’s
presence as something creepy and off. Nonetheless, France’s first thought is
that it may be General Winter, ghosts, or Russia’s old emperors following him.

5)   Why does Russia say KolKol?

 This part is theory. It hasn’t been confirmed
in canon.

A fictional tale included in the fourth original chapter of
the webcomic details how the Allied leaders – Roosevelt, Stalin, and Churchill –
reacted when the plane they were on was suddenly attacked by a demon [x]. As the
demon sets out to destroy the plane’s engine, neither Churchill’s nor Roosevelt’s
negotiations were able to stop it.

It’s only when Stalin threatens to throw the devil into a
Kolkhoz – a collective farm, commune – that the demon disappears. The story ends with
this quote:

“At the moment the
devil heard those words,
it flew away, never to be seen again.

From the kolkhoz that even the devil fears.”

The reason I mention this story is because,
in the panel above, we see Russia muttering “kolkolkol” in reaction to
Lithuania’s unfavourable remark aimed at his “old-fashioned” uniform.

If that’s the case, then perhaps
when Russia mutters “kolkolkol” it’s a form of repelling anything that he doesn’t
like, similar to how a priest repels a devil.

Bonus: Although unmentioned, there’s
also the curse that Rasputin allegedly cast on the Russian royal family before
he died.

What does England have to do with this? 

You’ll notice that throughout the
manga, England is consistently wary and distrustful of Russia.

Ex: During WW2, Russia offers
England some of his tea. England’s immediately skeptical and suspects Russia of putting
something strange in it [x]. 

Ex: England calls Russia a psychotic bastard when the latter’s
heart falls out during a meeting. England had initially thought that the heart
wasn’t Russia’s.

Ex: England doesn’t hesitate to express his desire to kick
Russia out of the G8.

Ex: When he falls asleep during a world meeting, England has
a weird dream and blames it on Russia.

As mentioned above, the hostility isn’t only one-sided.
Russia doesn’t always get along with England either.

Ex: During the Splendid Isolation strips, England
acknowledges that Russia wants him dead

–

at that time [x].

Ex: In the same strip where England falls asleep during a
meeting, Russia’s solution to wake him up is to hit him with a sickle.

Evidence of a demonic presence:

Given the evidence I’ve presented,
my answer is that because England is magical himself, he’s able to sense the
dark presence emanating around Russia. In other words, Russia spooks him.

Ex: England claims that Russia
being depressed is a dangerous omen.

Ex: During the 2013-2014 Christmas Event, right
before Russia arrives [with America and Japan], all ghosts, mythical beasts, fairies,
and monsters present feel a dangerous aura [x].

They later flee to avoid being
taken over by something evil. I don’t think this is a coincidence [x].

It’s for this reason that I believe
that Russia is once described as the person that England doesn’t want to meet
in private [x].

In the Merry Halloween strip, the
gag is that England and America host an annual competition where the two
attempt to out-scare each other. England brings a fairy friend to scare
America. Meanwhile, America uses Russia. The fact that England’s terrified of
Russia makes sense if you look at it from the perspective that Russia harbors
many dark spirits around him.

In sum, it would seem that England
is hostile toward Russia because he’s canonically cursed, can give curses
himself, and has malevolent spirits that follow him.