1715, Sweden entered the war against Vladimir-Suzdal on the side of Novorossiya, to get the once lost parts of Finland and Estonia back, which happened too. But 1785-87, Novorossiya attacked the weakened Sweden, conquered Finland, Estonia.
Since the anti-Russian War
In September 1848, Swedish troops landed at Oulu, started the liberation of Finland. During the Winter of 1848/49, northern Finland was liberated too. In the peace of Constantinople (1852, May), Finland and Estonia became Swedish again.
But when Germany invaded Sweden 1879, Novorossiya used the opportunity to reclaim/-annex Finland and Estonia in Scandinavia.