Act I.—­The chieftain of the North Quarter of Iceland, Kolbein the Young, lies sick unto death from the after-effects of an old wound and sends for his kinsmen and other nobles of the Quarter.  While delivering his message to them, Thorolf, his favorite (secretly the lover of the chieftain’s wife, Helga), and long a thorn in the flesh of these proud men as an upstart, infuriates them anew by his insolent bearing.  Obedient to the call of their chief, they assemble about him to determine on measures for the defence of the land, and to learn of the disposition of his dominions.  The weak Brand is given his lawful share, which agrees well enough with Lady Helga’s self-seeking plans of uniting all the land under her and Thorolf’s rule.  The more forceful Broddi is entitled to the other half; but when Kolbein, very conveniently for her, becomes delirious she substitutes Thorolf’s name instead, shrewdly taking the precaution of compelling Brand by force of arms to swear him an everlasting truce—­ostensibly to atone for having offered an insult to Brand.

Act II.—­Broddi now assumes the leadership of the outraged nobles, Brand being bound, as he thinks, by his oath, and incapable of strongly opposing their intention to kill Thorolf.  By chance, and in fulfillment of a prophecy, Thorolf seeks refuge from a snowstorm in a wintry cave and there is forewarned of his impending death by Woden himself.  He is surprised by the allies and slain.  But no sooner is their purpose accomplished than Helga, his protectress, appears on the scene and smilingly assures them of retribution awaiting them.  Her information that Kolbein is on the road to recovery strikes the nobles with dismay.  Broddi immediately decides on assuming the aggressive; but on Brand’s suggestion they choose first to cleanse themselves before the world by receiving absolution for their deed from Bishop Botolf at Holar.

Act III.—­Here Kolbein puts them to flight.  He, in his turn, must flee before Broddi’s superior forces, but not without audaciously carrying along the bishop, who in his fear and rage has the Treuga Dei rung over the land.  This frustrates the immediate pursuit by Broddi.

Act IV.—­While the truce is still in force, Lady Helga visits Brand’s wife, Jorun.  Childless herself, she desires to foster up one of Jorun’s sons in her own cruel way, promising, in return, to procure an honorable peace for Brand; or else, to destroy him.  The loving mother staunchly refuses.  But soon the weakness of Brand’s situation becomes evident.  Unable to act with the requisite force and severity, he has lost the confidence of his dependents who fear to rise against the superior genius of Kolbein.  The last hope departs when Broddi learns through a (forged) letter that his fortifications are accessible to Kolbein by subterranean passages.  Utterly dismayed, the allies decide to throw themselves upon the mercy of Kolbein the Young.  Brand’s wife follows them, disguised in male attire.  She knows that Helga thirsts for his life, but also that she has sworn to spare him if any one were found willing to give his life instead.