Cossack numbers increased when the warriors were joined by peasants escaping serfdom in Russia and dependence in the Commonwealth. Attempts by the "szlachta" to turn the Zaporozhian Cossacks into peasants eroded the formerly strong Cossack loyalty towards the Commonwealth. The government constantly rebuffed Cossack ambitions for recognition as equal to the "szlachta". Plans for transforming the Polish–Lithuanian two-nation Commonwealth into a Polish–Lithuanian–Ruthenian Commonwealth made little progress, due to the unpopularity among the Ruthenian "szlachta" of the idea of Ruthenian Cossacks being equal to them and theirs elite becoming members of the "szlachta". The Cossacks' strong historic allegiance to the Eastern Orthodox Church also put them at odds with officials of the Roman Catholic-dominated Commonwealth. Tensions increased when Commonwealth policies turned from relative tolerance to suppression of the Eastern Orthodox Church after the Union of Brest. The Cossacks became strongly anti-Roman Catholic, an attitude that became synonymous with anti-Polish.