Grendel makes his way to the hall from the moors. When he arrives he forces open the door. He is ready for blood, and is gleeful when he sees all the sleeping warriors and contemplates the deaths he will inflict.
But Beowulf is awake and watches Grendel's every move. Grendel strikes suddenly and gobbles one man up. He comes closer and raises a talon to attack Beowulf. A fierce fight ensues. Beowulf gets Grendel in a grip from which the monster cannot escape. Benches are smashed in the struggle. Grendel howls in pain. The monster knows he is beaten, but Beowulf refuses to let him escape alive. Other Geat warriors join in the struggle, thrusting at Grendel with their swords, although they cannot hurt him because by magic the demon has made their weapons harmless.
Grendel's strength begins to fail him. Beowulf rips his shoulder off, and Grendel, fatally wounded, creeps back to his lair. The victorious Beowulf has fulfilled his promise to the Danes. In triumph he displays Grendel's severed shoulder and arm.
In the morning, men come from far and wide when they hear what has happened. Grendel left a bloody trail and then dived into his den in the marshes to die. After all the visiting warriors have seen the evidence of Beowulf's feat, they depart full of praise for him. A minstrel at Hrothgar's court sings in praise of Beowulf's triumphs. The minstrel also sings of another great hero, Sigemund, who killed a dragon that guarded a great treasure. The minstrel also sings of King Heremod, who had been defeated in battle, letting his own nobles down, unlike Beowulf, who had successfully defended the land.
The Danes celebrate by racing their horses. In the mead-hall, Hrothgar gives praise to God for the ending of the menace from Grendel. He also praises Beowulf, adopting him in his heart as a son, and bestowing worldly goods upon him. He has made himself immortal by his glorious actions.
Beowulf then tells the story of the fight with Grendel. The warriors eye the claw of Grendel that is hanging from the eaves. It is as hard as steel, and the warriors agree that no sword blade would have been sharp enough to cut it.
The badly damaged hall is repaired and the women decorate it with weavings that they hang from the walls. When the hall is ready, everyone gathers for a victory feast. Hrothgar presents Beowulf with victory gifts: a gold standard, an embroidered banner, breast-mail, a helmet, and a sword. Then he gives him eight horses and a sumptuously designed saddle.
Hrothgar then presents gifts to each of Beowulf's men, and pays compensation for the one Geat warrior who was killed by Grendel.
The passage about the minstrel shows how history was preserved in such warrior societies. The minstrel is himself a historian ("a carrier of tales") who knows all the stories of the past. He is the king's poet, with an honorable position in the society. He sings of past heroes, such as Sigemund, but he also composes on the spot, to a strict format ("strict metre") the emerging story of Beowulf. Everyone sits in the mead-hall, the center of community life, and listens to the songs of the minstrel. Readers of Homer's Odyssey will recognize that the minstrel in Homeric times played a similar role. The minstrels' tales help the society to encode its ideals, remember its origins and forge its common identity.
The minstrel's mention of King Heremod, in his song about Sigemund, reveals an aspect of the poet's technique in Beowulf. He makes many contrasts between pairs of characters, often to make a moral point about right and wrong, about those who fulfill their social responsibilities and those who do not. Here, Heremod behaved unwisely and was defeated in battle, letting his own nobles down. He is compared unfavorably to Beowulf, the warrior who successfully defended the land.