Receiving his orders, Ivar drew his men together, reformed the ranks, and turned north to strike at the Frankish main force where Charles the Bald held command.
Ivar’s unit — the spearhead of the campaign — numbered a thousand armored men. He himself wore a cuirass sewn with plated scales over a layer of mail, and, with his iron helm, the total weight of his armor came to an astonishing fifty jin — roughly twenty-five kilograms.
Under the gray wolf banner the heavy infantry marched with ponderous, inexorable steps toward the Frankish shield wall. After a short, sharp clash, the Frankish line began to withdraw northward of its own accord.
By instinct Ivar did not try to smash through in a single, reckless burst. He pressed steadily, driving the enemy back, inch by measured inch, toward the banks of the Seine.
On the western command platform, watching Ivar’s advance, Rurik felt the battle drifting toward their grasp; victory already seemed eight parts won. He waved his flags and signaled his own detachments to wheel east and complete an encirclement, to sever at once the Franks’ path back to the bridgehead.
Charles — the Bald — saw the danger coalescing. He understood now that the thunderous Viking flank to his west had been largely a show: noisy, impressive, but not decisive. The real threat lay elsewhere — in the thousand heavy footmen to the south and in the two pike formations sweeping in from the east.
Yet knowing the tactic and stopping it were two separate things.
Once the southern field was out of his control, the Frankish forces remaining numbered over six thousand. Their tally impressed at a glance, but the men themselves were poorly organized conscripts with sagging morale. Under simultaneous pressure from the west and the south, those six thousand masses drifted northward in panic toward the riverbank, a single heaving flock of disordered sheep.
As the hours passed, Rurik issued command after command, each one snipping another thread from the enemy’s hope of escape.
"The southwest corner is loosening — send ’White-hair’ Oleg to relieve Ulf’s unit."
"Nils’s archers, be ready. Follow behind Lennard and Theowulf. When you come within range, pepper the Frankish center with arrows. Do not aim for a quick, concentrated slaughter; rather, keep up a steady, prolonged barrage to impede their reorganizing."
"Om is charging too fast and falling out of step with Lennard — damn it, slow him down!"
"Bjorn’s men are done resting. Send them to the southern field to cover Ivar’s rear and prevent stray Frankish horsemen from disrupting his assault."
By one in the afternoon, with five hundred light infantry in support, two additional pike formations had skillfully worked their way to the eastern flank, sealing off any retreat from the Frankish lines back to the bridgehead.
Through a sequence of well-timed movements, Rurik had at last realized the scheme they had discussed before the battle: the Frankish main force was now corralled along the Seine.
He sat cross-legged upon the platform, the field at his feet like a living tapestry. A shieldman pressed a wineskin of water into his hand. He drank half, dabbing the rest across his sweating face.
A warm breeze brushed his cheek and lifted a loose strand of hair. He tilted his head to the sky where clouds rolled white and endless, sunlight bathing him as if he lay in a heated bath.
"Armies have no constant form; water has no constant shape. By changing with my foe I have won," he thought. He felt a clear, quiet conviction: after this day his capacity to command forces under ten thousand would no longer be in doubt.
At two o’clock in the afternoon the Franks launched five successive attempts to break out, arrows raining from three directions. Each sortie was beaten back. As the fighting ground shrank, the six thousand soldiers were forced into a single, frantic crush at the river’s edge — and, with mounting helplessness, they flowed toward the shallows.
Word of the king’s peril raced over to the Île de la Cité. Thirty or so riverboats shoved off to offer aid. Viking longships surged to meet them and the two fleets became entangled; the Franks’ usual tactic of setting fire to boats proved useless in the melee.
Half an hour later a fast skiff reached the bank, took Charles the Bald and a dozen great lords aboard, and lurched away from the shore.
"I’m a cousin twice-removed of the Count of Orléans!" one cried.
"Take me! I will give you two vineyards at Bordeaux!" begged another.
"Sire, will you abandon this humble cleric?" a priest wailed.
Their voices mingled with the splashing oars as the skiff strained west toward the island. A few desperate men clung to the gunwales, unwilling to let go. As the boat threatened to capsize with the weight, and with the king’s gaze coldly permissive, the captain gave the order — his sword flashed and severed fingers grasping the planks; severed digits thudded and rolled across the deck, a ghastly, shuddering sight.
At last, under the frantic cover of the remaining Frankish boats, Charles returned to the Île de la Cité and found the queen and her ladies ashen with fear.
"Do not be alarmed," he called. "The island is naturally defended. These savages cannot scale—"
Before he could finish a noblewoman rushed forward and gripped his sleeve.
"Sire, where is my son? Why did he not follow you?"
She and the other ladies swept past the guards and began to demand the fate of their sons, husbands, fathers, brothers.
By three in the afternoon, the king had fled and the morale of the remainder collapsed. They laid down their arms and surrendered; the battle on the Seine was over.
Viking losses numbered approximately thirteen hundred, the majority from the southern fighting — in trying to neutralize the Frankish cavalry, Bjorn, Ulf, Gunnar and the two pike formations had paid dearly.
Frankish casualties were roughly fifteen hundred dead; close to six thousand survivors were taken captive and several hundred scattered as deserters fled the field.
After tallying the cost and the capture, the nobles held a brief council. The victory had been splendid: the Frankish main force was annihilated while Viking losses remained comparatively restrained. The consensus — unanimous and mercenary — was to seize Paris, pillage well, and then return to Britain richer than before.
Before sunset the Vikings pitched their siege camps outside the southern bridgehead. The proximity of farmhouses and a nearby market hastened the construction; tents rose and platforms sprung up with surprising speed.
By custom and by acclaim, Rurik was named commander of the siege. He would oversee the camp and the forthcoming operations. The nobles dispersed: Ivar and Bjorn took a few hundred hands northward in search of their fathers; the rest scattered to find food, coin, and diversion.
As for siegecraft, Rurik’s mind went first to blockade.
A few days earlier, when the army passed Rouen, the Franks had stretched an iron chain across the river. The Vikings had seized the southern fort, cut one end of that chain loose, and gravity had dragged it to the riverbed.
Now Rurik planned to take the north bank at Rouen. There the chain’s other end was fixed. If they could haul it from the water, transport it upriver by ship, and reattach it, they could bar the eastern approaches of the Seine above Paris.
"With the Frankish field army destroyed, only a handful of palace guards and a thousand or two of worthless conscripts remain on the Île," he said to himself. "We will build siege camps on both banks outside each bridgehead and string a chain upstream to seal this city in the river’s grasp."