Was the bolshevik revolution a turning point in history?

Yes. Beginning in 1917, a series of revolutions destroyed the Russian royal system, removed Tsar Nicholas II from power, and formed a provisional government. Later that year, the powerful Bolshevik Party took over and slowly but surely replaced the provisional government throughout the country. This was the small beginning of the U.S.S.R. years later, but first wars had to be dealt with. In 1918, the Bolsheviks signed a treaty with Germany removing Russia from World War I. This was followed by several years of civil war between the Reds (bolsheviks) and Whites (anti-bolsheviks) as the Reds slowly developed their power. In 1918, the Reds murdered Tsar Nicholas and his entire family, partly in hopes of demoralizing the Whites who had hoped to put Nicholas back on the Russian throne.

As the Bolsheviks consolidated power, they became the Communist Party and adopted a cult of personality with Vladimir Lenin as the sole voice and face of the party. Lenin handled the role adeptly and was firmly in control of the party by the end of the civil war in 1922. In the course of 5 years, the world's largest nation had gone from being a powerful monarchy to a republic of sorts, albeit an autocratic republic with a lot of monarchical features.

The final movement of the great turning point was the determination of Lenin's successor - Lenin began suffering strokes in 1922 and was dead by 1924, a national hero and national saint. Two men had been positioning themselves to take over the Communist Government. Openly, and rightfully so, war hero of the Revolutions and Minister of War Leon Trotsky was apparently the most powerful man in Russia and seemed the most likely successor to Lenin as head of the Russian Communists. However, working quietly behind the scenes was Joseph Stalin, who had been slowly working himself into command of almost all the nation's bureaucracy. With firm control of almost every political organization in Russia in his hands, it didn't take Stalin long to get rid of Trotsky and a few other competitors.

By January of 1928, Stalin was in complete charge of Russia and the Communist Party, a new cult of personality was in place, and the Boshevik Revolutions that had begun 11 years earlier had finally reached the end of their road, for better or for worse.