The answer is October Manifesto, also officially known as "The Manifesto on the Improvement of the State Order". This was the answer of Tsar Nicholas II to the Russian Revolution of 1905, who basically resisted doing so, but he put it under pressure. This manifesto provides basic human rights and a parliament called the Duma as the supreme legislature, without whose approval it was not possible to pass laws. It seems that this manifesto was the trick of Tsar Nicholas, because shortly after its entry into force, Autocracy began again to show its strength.
