That the Tsar, at the urging of his ministers, eventually made concessions to the people in 1905 was a large factor in his survival of the revolution. In the October Manifesto, the Tsar had promised the people a great deal of what they believed would make their lives better. The Tsar agreed to establish the Duma and granted basic civil rights, allowing people to set up their own political parties, and have freedom of expression. Stolypin also helped to further satisfy the people and to improve their lives by his series of land reforms following soon after the revolution of 1905. This apparent relaxing of the autocracy pacified the people enough for the tsar to maintain his position in 1905.
By 1917, making concessions was no longer an option: the people had seen that the Duma had only a nominal influence and was nothing more than a pacifier, the Tsar having dismissed the first Duma after only 73 days, the second lasting only a short while longer, and the tsar having the ultimate decision on all matters no matter what the Duma might think. The Russian people would not settle for being bought off with promises a second time: by 1917 they would only be happy with the abdication of the Tsar.
Although the turning of the Cossacks on the people caused the problem of the Bloody Sunday Massacre, the loyalty of the army to the Tsar was a key factor in his retention of power. This meant that he was protected from the revolution because he had the military power necessary to put down the striking and to protect himself from any violent rebellion among the common people. The opposition was a disorganised rabble, and there was no way that they could effectively oppose the Tsar while he had the army supporting him.
However, by the 1917 revolution the Tsar no longer had this support from the troops and it was perhaps this key factor more than any other which eventually led to his downfall. The Russian entry into the First World War had led to millions of young men being conscripted into the army rather than choosing it as a lifetime career. This meant that not only were the majority of the army unwilling, they were also disloyal to the Tsar, as most had come from the factories where socialism was growing and there was great dissatisfaction with the autocracy. For these men, the shooting of 40 striking workers on 11th March was enough to prompt the soldiers, even the dreaded Cossacks, to support the striking workers rather than the Tsar, and so. It was not only the ordinary soldiers who were against the tsar: since Nicholas made himself commander of the troops in 1915, the generals had lost faith in him due to his military failure, and began to take orders from the Duma rather than the Tsar. With no armed forces to control it, the whole situation descended into disorganised anarchy in 1917.
Although the October Manifesto may have saved the Tsar in 1905, his failure to fulfil the promises stipulated therein played a large part in his downfall in 1917. The emergence of the free press after 1905 granted the right to express opinions by publication meant that the Tsar was widely criticised to the public for the first time, whereas previously none of his wrong-doings had ever been made known, and he was viewed as ordained by god. Now however the Russians began to see him as fallible and to question his actions, leading to further unrest.
Similarly, and perhaps most importantly, the Duma in 1917 provided a viable alternative to the autocracy which had not been present in 1905. Ironically, just as freeing the serfs had led to them wanting more and assassinating Tsar Alexander II, Nicholas’ grandfather, so granting the people their Duma in 1905 in part led to the eventual downfall of the Tsar in 1917.