A world similar to our own, until the 19th century where technological progress picked up speed. When the american civil war was going, they already had developed the radio and used it at its full potential and by the end of the century, it was becoming household items.
The great divergence from our world however came in 1908. The Tunguska event brought with it something other than a mysterious explosion in the middle of Siberia. It changed the world , and humanity was no longer alone on planet earth, and a new world leader, power and religion dawned.