Peter tempered this new army in attacks on the Swedish holdings of Livonia and Ingria on the Baltic shore. Once he was sure that Charles was heading south, he ordered his field marshal, Boris Sheremetev, to attack the lightly defended colonies, whilst also sending a division south, to delay Charles XII and give Peter time to finish mending his forces. At the end of 1701, Sheremetev met a vastly outnumbered Swedish force on the field at Erastfer in Livonia, soundly defeating them; he repeated the feat again at Hummelshof in July 1702. These two victories, the first significant ones in the Russian campaign, helped boost Russian morale after the catastrophe at Narva. Peter then sent Sheremetev to Ingria, where he mopped up Swedish forces on the Lake Ladoga isthmus. October 1702 marked the taking of the Swedish fort of Nöteborg. In May 1703, Peter captured Nyenschantz fortress. He chose a spot at the mouth of the Neva, surrounded by marshes, to establish his fortress of Saint Petersburg. Originally an outpost against the Swedes and Peter's "window to the west", the fortress would later grow into one of Russia's largest and most important population centers, and under Peter, Russia's capital.