The eastern Finnic Votes, Korela (interpreted as Karelians in general or more specifically as the Karelians on the southwest coast of the Ladoga) and Izhorians are all mentioned as allies of Novgorod, said to have been fighting against the Yem even without Novgorod's direct involvement, possibly over control of land area in central and eastern Finland; this territorial feud manifested in annual retaliatory expeditions that featured merciless treatment of the settlers of the opposing tribe.
The earliest possible mention of hostilities is from the Laurentian Codex which records in passing that the Novgorodian Prince Vladimir Yaroslavich was at war with the "Yam" in 1042 AD.
Votes, today almost extinct, lived south of the present-day Saint Petersburg, probably making this the deepest attack that Yem ever made into Russian territory.
[11] After a long pause in open hostilities—at least in the chronicles—a Novgorodian called Vyshata Vasilyevich led his troops against Yem in 1186, returning unharmed with prisoners.
He may have been in a military role similar to that of Jon Jarl, who allegedly spent nine years overseas fighting against Novgorodians and Ingrians at the end of the 12th century.
[20] The crusade is only known from later legends that presented the expedition (if it ever took place) as a Christian mission, headed by a saint king to baptize heathens.
Some historians have seen it as a direct reaction to the failed Yem expedition in 1149, associating it with the co-operation mentioned by the Pope 20 years later.
After having secured his power in Novgorod by 1222, Grand Prince Yaroslav II of Vladimir organized a series of attacks against Estonia, Yem and Karelia.
[16]The Yem retaliatory expedition in summer 1228 against Ladoga, allegedly with more than 2000 men[26] ended in disaster, as described by the Novgorod First Chronicle.
The same night they asked for peace, but the bailiff and the people of Ladoga did not grant it; and they killed all the prisoners and ran into forests, after abandoning their ships.
Based on Papal letters from 1229,[28] the unknown Bishop of Finland took advantage of the chaotic situation by taking over non-Christian places of worship and moving the see to a "more suitable" location.
On the bishop's request, the Pope also enforced a trade embargo against Novgorodians on the Baltic Sea, at least in Visby, Riga and Lübeck.