Marx found the program negatively influenced by Lassalle, whom Marx regarded as an opportunist willing to limit the demands of the workers' movement in exchange for concessions from the government. However, at the congress held in Gotha in late May 1875, the draft program was accepted with only minor alterations by what was to become the powerful Social Democratic Party of Germany (SPD). Engels had Marx's programmatic letter published much later, in 1891, when the SPD had declared its intention of adopting a new program.