Greek interest in reviving the Olympic Games began with the Greek War of Independence from the Ottoman Empire in 1821. It was first proposed by poet and newspaper editor Panagiotis Soutsos in his poem "Dialogue of the Dead", published in 1833. Evangelis Zappas, a wealthy Greek-Romanian philanthropist, first wrote to King Otto of Greece, in 1856, offering to fund a permanent revival of the Olympic Games. Zappas sponsored the first Olympic Games in 1859, which was held in an Athens city square. Athletes participated from Greece and the Ottoman Empire. Zappas funded the restoration of the ancient Panathenaic stadium so that it could host all future Olympic Games.
The Panathinaiko Stadium hosted Olympics in 1870 and 1875. Thirty thousand spectators attended that Games in 1870, though no official attendance records are available for the 1875 Games. In 1890, after attending the Olympian Games of the Wenlock Olympian Society, Baron Pierre de Coubertin was inspired to found the International Olympic Committee (IOC). Coubertin built on the ideas and work of Brookes and Zappas with the aim of establishing internationally rotating Olympic Games that would occur every four years. He presented these ideas during the first Olympic Congress of the newly created International Olympic Committee. This meeting was held from 16 to 23 June 1894, at the Sorbonne University in Paris. On the last day of the Congress, it was decided that the first Olympic Games, to come under the auspices of the IOC, would take place in Athens in 1896. The IOC elected the Greek writer Demetrius Vikelas as its first president.
Information sourced from Wikipedia.