Treaty of Hadiach
Only some of the Ruthenian "szlachta" of the Chernigov region, who had their origins in the Moscow state, saved their lands from division among Cossacks and became part of the Cossack "szlachta". After this, the Ruthenian "szlachta" refrained from plans to have a Moscow Tsar as king of the Commonwealth, its own Michał Korybut Wiśniowiecki later becoming king. The last, ultimately unsuccessful, attempt to rebuild the Polish–Cossack alliance and create a Polish–Lithuanian–Ruthenian Commonwealth was the 1658 Treaty of Hadiach. The treaty was approved by the Polish king and the Sejm, and by some of the Cossack "starshyna", including hetman Ivan Vyhovsky. The treaty failed, however, because the "starshyna" were divided on the issue, and it had even less support among rank-and-file Cossacks.