After the impoverishment of the northeastern part of Russia by Mongols, the cities of Novgorod and Pskov were unguarded and became the easiest spot for attack by the German and the Swedish hosts. The Swedes were the first to try to occupy Russian lands. In 1238 the Swedish king got the permission of the Pope of the Rome to start the crusade campaign against Novgorod. The indulgence of sins was promised to those participating in the campaign.
In 1239 the Swedes and the Germans started negotiations on planning the campaign. The Swedes had occupied Finland by that time and were to attack from the north, by the river Neva. The Germans were to start with Izborsk and Pskov. The Swedish troop was conducted by yarl (prince) Ulf Phasi and the king's son-in-law yarl Birger, the founder of Stockholm in the future.
Novgorod people knew that the Swedes were going to attack them and make them adopt Catholicism. Thus it seemed to them even worse than Mongol's invasion.
In summer of the 1240 the Swedish troop headed by Birger arrived on board the ships by the Neva and stopped in the mouth of the river Izhora. It consisted of the Swedes, the Norwagians, and the representatives of the Finnish tribes, planning to go straight to the Ladoga and then directly to Novgorod. There were also catholic bishops holding the crosses in one hand and the swords in another. The enemy's camp had been located near the Izhora's inflow to the Neva. Birger, sure in his victory, sent a message to prince Alexander claiming that he was already conquering his land.
At that time allied local tribes both on land and water guarded the Novgorod boarders. The Izhorian tribe, which had already adopted Christianity, guarded the sea boarder near the Neva on both banks of the Finnish gulf. The dean of the Izhorian land Pelgusii was the first to notice the approaching Swedish fleet on the dawn of a July's day in 1240 and hastily sent a man to report about it to the prince Alexander.
The prince's decision was to attack the enemy unexpectedly. There was no time for collecting the troop, as there was no time for calling 'Veche' (public meeting). Alexander didn't have time to wait for the troops sent by his father Yaroslav, or for the recruitment of new ones throughout the Novgorod lands. He decided to attack the Swedes with his own team and the group of Novgorod volunteers. According to the tradition, they gathered near the Saint Sophia's Cathedral to pray and be blessed by their highest priest Spiridon. Their way was along the river of Volhvy past the Ladoga, where the brigade of ladozhans, Velikii Novgorod's federates, joined them and to the mouth of the Izhora.
The conquerors' camp, set up in the mouth of the Izhora, wasn't guarded, as the Swedes didn't expect the attack. The enemy's ships were rocking on the water, and white tents were scattered along the coast with Birger's golden tent at the head. On the 15th of July at 11 o'clock in the morning the Russian troop suddenly attacked the Swedes. The attack was so unexpected that the Swedes didn't even have time to take their swords.
Birger's troop was caught unprepared, so it couldn't resist. The brave onrush of the Russian troop forced the opponents to the banks of the river. On the way they cut the bridges connecting the ships with the ground, and even seized and burnt three ships of the enemy.
Novgorod citizens fought with all their courage. Alexander himself beat a great number of the Swedes, and put the seal of his sword on to the king's face. The prince's assistant Gavrilo Oleksich followed Birger to the Swedish boat astride the horse where he was dropped of to the water. After what he plunged into the battle again and killed another noble Swede named Spiridon on the spot. Another Novgorod citizen put his way through the crowd of the enemies using the axe. The prince's huntsman Yakov Polochanin with his long sword and other brave teammates followed him. Prince's otrok beat his way to the center of the camp and cut the basis of Birger's tent. The troop of Novgorod volunteers drowned three Swedish ships. The rest of the enemies had to escape on the remaining ships. The losses were insignificant whereas the three Swedish ships were loaded with only noble people, leaving the others on the Russian land.
The victory over the Swedes was of the great political importance. It proved that Russian people hadn't lost their valor and were still able to protect themselves. The Swedes failed to capture the coasts of the Neva and the Finnish gulf and to cut Novgorod from the sea. Repulsing the Swedish attack from the north Russians defeated the possible cooperation of the Swedish and the German conquerors. In case of German attack the right flank and the rear of Pskov's seat of war was safely protected.
Tactically important was the role of the 'guardians', who first saw and reported about the approaching enemy. The governing factor of the victory was the element of surprise, as the enemy was caught unexpected and couldn't repulse. The chronicler pointed out the extraordinary courage of Russian warriors. After this victory prince Alexander Yaroslavich was named 'Nevski' in honor of the river Neva. He was in his twenty first year.