What was the provisional government’s fatal mistake?

The authority of the Tsar's government began disintegrating on 1 November 1916, when Pavel Milyukov attacked the Boris Stürmer government in the Duma. Stürmer was succeeded by Alexander Trepov and Nikolai Golitsyn, both Prime Ministers for only a few weeks. During the February Revolution two rival institutions, the imperial State Duma and the Petrograd Soviet, both located in the Tauride Palace, competed for power. Tsar Nicholas II (1868-1918) abdicated on 2 March [15 March, N.S.], and Milyukov announced the committee's decision to offer the Regency to his brother, Grand Duke Michael, as the next tsar. Grand Duke Michael did not want to take the poisoned chalice and deferred acceptance of imperial power the next day. The Provisional Government was designed to set up elections to the Assembly while maintaining essential government services, but its power was effectively limited by the Petrograd Soviet's growing authority.

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