The operation of the new Czechoslovak government was distinguished by stability. Largely responsible for this were the well-organized political parties that emerged as the real centers of power. Excluding the period from March 1926 to November 1929, when the coalition did not hold, a coalition of five Czechoslovak parties constituted the backbone of the government: Republican Party of Agricultural and Smallholder People, Czechoslovak Social Democratic Party, Czechoslovak National Social Party, Czechoslovak People's Party, and Czechoslovak National Democratic Party. The leaders of these parties became known as the "Pětka" ("pron. pyetka") (The Five). The Pětka was headed by Antonín Švehla, who held the office of prime minister for most of the 1920s and designed a pattern of coalition politics that survived until 1938. The coalition's policy was expressed in the slogan "We have agreed that we will agree." German parties also participated in the government in the beginning of 1926. Hungarian parties, influenced by irredentist propaganda from Hungary, never joined the Czechoslovak government but were not openly hostile: