How would the world be different if Peter the Great had never been born?
For one, whoever asked this would not be around. But jokes aside, let's look at who would take throne after the death of Tzar Alexei, Peter's father. Most likely, it would still be his sickly half-brother Fedor III, who died six years after his father, in 1682, a month before his 21st birthday. Then, due to him being childless, the throne would go to his younger brother, Ivan. Who is 16 and not capable of ruling due to poor health. Their older sister (25) would seize power, and maybe become the ruler of Russia in 1696, when her brother dies. But in 1696, Russia is a country were women are not viewed as completely incapable of governing a country. Europe was not much better at the time in terms of women's rights. So, we would probably have Time of Troubles #2. As for what happens after 1696, I can't calculate the butterfly effect.