The Mongol invasion not only demolished Ancient Russia but also affected regular commercial relations. The surviving Novgorodian Republic became the basic trading partner of the new monopolist of Baltic commerce, the Ganza Union of towns. Due to slow development of transportation infrastructure Novgorod could not accept the new types of marine merchant vessels of large displacement. The role of the main commercial ports passed on to Danish Revel and German Narva where Russian merchants delivered their goods on river boats. After monopolizing the sea trading Ganza forced out Russian merchants from the shipping market on Baltic Sea and secured drastic reduction of export pricing. The structure of goods flow also changed.
Now Novgorod became the main opening for importing silver and gold to Russia from the West. Novgorod of the 14th – 15th centuries was the basic centre of casting of silver bullions in which Russian principalities paid the levy to the Horde. The import was so huge that in 1334 Ibn-Batut wrote about the richest silver mines functioning in the north of Russia. Besides, through Novgorod Russia received non-ferrous metals (copper, tin, lead, zinc), cloth, salt, grain, weapon, foreign wines and beer.
Novgorodian export was first of all represented by the furs. 81% percent of all furs passing through the Strait of Eresuni came from Novgorod. Wax took the second position providing 73 percent of Revel re-export. Leather took the third place in production of which 19 percent of Novgorod craftsmen were engaged. The special item was Chinese silk brought by the merchants from Caspian Sea. Rapid increase of trading volumes lead to quick intensification of navigation and it`s not surprising that the period of peak prosperity of Ganza accounts for appearance of Vitaliers and Likedelers pirate republics on Gotland and Ruecken islands which were prospering for many decades due to buccaneering.
A small part of trading was transacted through Swedish Viborg towing small ships along Vuoksa to Ladoga Lake. Voyages to Caspian Sea, sailing to Viborg, Narva and Revel intensified the river shipbuilding in Volkhov region. It is known that up to 250 flat-bottomed boats at a time took part in voyages to Caspian Sea and overall quantity of Novgorod fleet according to the western sources reached 3500 vessels. No wonder that frequently there were incidents of mass loss of caravans. For example, in 1408 “the Great storm” wrecked Novgorodian vessels with about thousand men aboard. We managed to discover at the bottom rather many fragments of small wooden vessels that may be referred to the Ganza period. Sonograms draw the image of the bodies coinciding in size and construction with Ganza cogs but their identification requires expensive underwater digging at the depth of 35-40 meters and so far they have to wait for their turn. Meanwhile they might conceal unique testimonies.