In 1908 the Imperial Russian Olympic Team arrived in London 12 days too late for the games because they were not using the Gregorian calendar yet.
The Olympic movement in general was just gaining momentum at that time. Baron Pierre de Coubertin founded the International Olympic Committee just 14 years before, in 1894, so regulations, as well as the total number of athletic categories, were still uncertain and not set in stone. The London 1908 Olympics lasted for six months, from April 27 to October 31, and embraced disciplines such as skating (there were no Winter Olympics back then) but failed to provide a comprehensive and conclusive report.
Until 1918 Russia lived according to the (Old) Julian calendar, which lagged two weeks behind the modern Gregorian calendar in use in Europe and North America. Many experts put it this way: Russia’s national team arrived in London two weeks later and missed some of the competitions; luckily enough, the Russians still had 4.5 months ahead of them.
“The Russian national team forgot that Great Britain had switched to the Gregorian calendar 200 years prior… When the Russian delegation started to sign up, it turned out that the Olympics were already very much on, and some competitions had already ended,” wrote the Russian news portal, Lenta.ru.