Let all sleep, while to my shame I see
The imminent death of twenty thousand men

Fortinbras is about as minor a character as can be in Shakespeare’s Hamlet (1599? 1601?). He is mentioned offhandedly a few times, such as Horatio’s re-telling of Hamlet’s father killing Fortinbras’ father in a duel in Act 1.1, or Claudius sending ambassadors to Norway to stave off an invasion. Hamlet bumps into a captain who encountered his men on the beach in Act 4.4. None of the main characters are particularly invested in him or the danger he poses; interpersonal conflicts are far more important.

Hamlet. Who commands them, sir?
Norwegian Captain. The nephew to old Norway, Fortinbras.

He is not the focus, but he is an omnipresent threat. Unlike an Outside Context problem, he is one which the characters are well aware of, and which they make minor efforts to placate. Yet, at a time, when they ought to be presenting a united front against a foe who is definitely just going to attack Poland and not conquer Denmark to avenge his father’s murder, they are instead caught up in a different paternal murder mystery. There is so much politicking about who knows what when and how, and who will play three-dimensional chess to understand whose motivations, that the Damocletian sword of a literal army invading the country is pushed aside for the (admittedly much more interesting) attempts to gauge the king’s guilt via his reaction to a play, or soliloquizing in a graveyard about better times.

This is not terribly surprising.

Fortinbras is something they don’t want to think about, and so he is treated as someone who does not exist. He’s not a person they can affect in any meaningful way. The idea that, for example, the King’s spymaster Polonius would send agents to check on Fortinbras’ plans, the way he does to make sure his son isn’t descending into a life of vice and debauchery, doesn’t fit into the play. It’s the wrong story — this is about Hamlet’s revenge, not Fortinbras’.

By the end of the play, taking many by surprise as the foreshadowing and ominous beach landings which are often omitted to cut down on the play’s four hour run time, Fortinbras and his men walk into the throne room as Hamlet dies. Every other character, save Horatio, is dead. Without having to expend any effort, he can unite Norway and Denmark under his rule.

Take up the bodies. Such a sight as this
Becomes the field but here shows much amiss.
Go, bid the soldiers shoot.

He gets his revenge, and a kingdom, without lifting a finger.

Try not to think too hard about all the other looming problems we’re well aware of, but choose to ignore in favor of more personal problems.