Emperor Peter I of Russia stands as one of the most venerated figures in the country’s history. Alexander Nevsky may have repelled the North European attacks to save Russia in the middle ages; Boris Godunov may have united Russia and gained independence from the Mongols; but it would be Peter the Great’s reforms that took Russia from a backwater to one of the greatest countries in the history of Europe.

On this day, December 20, in 1699, on the eve of a new century, Peter the Great took another step towards bringing Russia on par with the more advanced European nations by adopting the same calendar system. Thus did the New Year change to January 1.

This was just a superficial change in marking dates, not a switchover from the Julian calendar to the Gregorian (that would not take place until well into the 20th century – after Russia had sold off Alaska, in fact, surprising the residents with a three-week jump in dates). But Peter had other, greater accomplishments: the city of St. Petersburg (nee Leningrad) owes its existence to him, and a semblance of a democratic government.