The first recorded ancient Olympic Games were held in 776 B.C. in Athens, continuing every four years until 393 A.D., when the Roman emperor Theodosius I abolished them because of their pagan roots. The modern Olympic games began in 1896.
According to History.com, the first modern Olympic Games took place in Paris in 1896 and featured 13 participating countries. They have been held every four years since then, with a couple of breaks during the two World Wars. The Olympic Games took a big leap forward in 1924 when the Winter Olympics began. By that time, 44 countries were participating in the Summer Olympics. Since 1994, the Winter and Summer Olympics have alternated, with one set of games taking place every two years.