CanadianGoose
Banned
POTATO.
As it being said, Novgorod was always (ok, from approx. 1000 AD) dependent on grain shipments from Central Russia and did not have good agricultural lands for grain crops. Early (by 1400 AD) introduction of potato could create self-sustainable agriculture there. IOTL Muskovy did not as much conquer Novgorod as pulled it under Grand Dukes authority using grain dependence.
Otherwise one could try to re-route Polish grain trade toward Novgorod, but it IMHO would require too many changes in Eastern Baltic area and could actually pitch Poland against Hansa.
As it being said, Novgorod was always (ok, from approx. 1000 AD) dependent on grain shipments from Central Russia and did not have good agricultural lands for grain crops. Early (by 1400 AD) introduction of potato could create self-sustainable agriculture there. IOTL Muskovy did not as much conquer Novgorod as pulled it under Grand Dukes authority using grain dependence.
Otherwise one could try to re-route Polish grain trade toward Novgorod, but it IMHO would require too many changes in Eastern Baltic area and could actually pitch Poland against Hansa.