Background: The Original Ancient Olympic Games.

Quite a bit of information concerning the Ancient Games was preserved through the ages even before Google and Wikipedia became household names. While the exact origin of the games is a bit sketchy, it is known they took place for over a thousand years between 776 B.C. and 393 A.D. The games were played every four years.
Their importance in Greek society is apparent from the fact, the word, Olympiad, meaning the four-year interval between competitions, became an integral term in the Greek calendar.
The games were discontinued for religious and political reasons rather than lack of popular support. The Roman Emperor at the time, Theodosius the Great, was eager to make Christianity the official religion of the whole Empire and sought to have everyone, East and West, sing the same tune. These games were recognized as honoring a mythological hero, i.e. a Pagan God; therefore, he considered them inappropriate for the world he was shaping.
Originally, the games were a one day contest. They quickly evolved into a five-day happening, as more competitions were added. Initially, a foot race of approximately 200 meters was one of the highlights of the games. Then more races were added, including a more long distance race of perhaps 5 kilometers (a precursor of today's 42 kilometer marathon) that circled outside the stadium. In addition, a chariot race, boxing, wrestling and various track and field competitions were included.
The opening day festivities included religious rituals and the final day featured a banquet for all the competitors. The competitors were all young men who competed naked. International participation was limited as all the competitors had to be free men (ergo no slaves) who spoke Greek.

Now, on to the Modern Olympic Games and the question:

"Who's your Daddy?"

The Father of the Modern Olympics

Who? Actually, three men could be scrutanized for a possible paternity suit as all three had a role. All three were visionaries with similar goals. All three men were good men who were focused and dedicated to the cause. They were not interested in rewards or accolades and took action not "for goods or gear, but for the thing" (Weland's Sword - Kipling). There probably would have been greater cooperation and support had their lives been a bit more parallel. The first man died before the last one was three years old. The middle one connected the other two.
The three competitors are (in chronological order):
Evangelis (Evangelos) Zappas (1800 – 1865)
William Penny Brookes (1809 – 1896)
Pierre de Coubertin (1863 – 1937)

Also, there is a subsidiary question, "When did the first Modern Olympic Games took place?" The choices are 1859, 1866 and 1896. The two questions are interlinked.
 
In 1829, Greece broke free from the 400-year grip of the Ottoman Empire with one final War of Independence (1821 – 1829). In the subsequent Treaty of Constantinople in 1832, the three super powers of the time, the United Kingdom, France and Russia all sat at the table and played a role.

During the years leading up to Independence, the spirit of nationalism was stroked and stirred by several writers and poets. These included the Greeks, Rigas Feraios (1757 - 1798), Dionysios Solomos (1798 – 1857), and Alexandros Soutsos (1803 – 1863), as well as, “the mad, bad” British poet, Lord Byron (1788 – 1824). Byron even sailed to Greece to join the fray and died there of illness within a year. (A side note. Although Lord Byron, a member of the Parliamentary House of Lords, had totally burn up and destroyed the welcome mat for himself in his homeland before he reached age 30, became a national hero in Greece.)

These writers rekindled thoughts and discussions of the ancient glory days, when Aristotle and Plato philosophized in the public squares; when athletes competed in the Olympic Stadium; and, when Greece was the center of the world. This retro dream of splendors past was not limited to the skies of Greece; rather, it floated throughout Europe, especially in those countries that had participated in reshaping the new Greece. Into this world, three men who were to play apart in developing the present day Olympics were born. 

The last, but perhaps most significant was Pierre de Coubertin (1863 – 1937), an educator and historian who sought a utopian world built upon a paradigm of friendship, trust and fair play. He also sought to have his homeland, France, develop a more complete and well rounded educational model that included physical fitness as well as intellectual pursuits.

As a young boy he had seen his country soundly defeated in the War of 1870 (Franco-Prussian War). He saw his beloved Paris attacked; placed under siege and then defeated by a Prussian Army that marched proudly through the streets of the capital. He wondered, if the young men of France had been more athletically trained, would the outcome of war been different?

De Coubertin admired the educational programs in England and the USA and noted the incorporation of sports activities.  He also dreamed of a world where countries competed in sports rather than battled in wars.

He felt the ancient Olympic games were an excellent way of putting off war and encouraging fitness. They had been successful before, so he asked, “Why not, again?” Two other individuals, one in Greece and one in Britain, had held similar thoughts and had already put their concepts into action.

One of these, Evangelis Zappas (1800 – 1865) who died when De Coubertin was only a child, was a rich and well-connected Albanian Greek. Zappas was a high roller and man of action. He got the ball rolling in Greece by enlisting the support of the King Otto of Greece. He put up the cash; built buildings and pushed full speed ahead. His success was a mini games held in Athens in 1859 (a few years before de Coubertin was born) that were basically all Greek. After this success, the Greek games began to falter. Sporadically, a few more games were held over the next few decades. The more notable ones in 1870 & 1875. But by then, Zappas and the King were dead and the overseeing sponsors and bureaucrats lacked the decisiveness, spirit, money and Gusto of Zappas. 

The third Olympic enthusiast was a British doctor and magistrate, William Penny Brookes (1809 – 1896). Brookes was a link between Zappas’ games and De Coubertin dreams. Brookes greatly admired the spirit of the Zappas’ 1859 games as they paralleled his own efforts. To show his enthusiasm and support, Brookes sent a British 10 Pound note to award to a winner of an event. The Greek authorities decided to give Brookes’ gift to the winner of the Long Race (the predecessor to the marathon).

A decade prior to the Zappas games, in 1850, Brookes started an annual games competition in his Central England hometown. By 1866, this small town effort had spawned all British, National Olympian Games that were held in London and attracted over 10,000 spectators. By 1877, Queen Victoria’s 40th Jubilee, King George I of Greece reciprocated Brookes’ earlier support of the Greek games, by sending a Silver Cup trophy to honor the occasion.

In 1890, De Coubertin traveled to London to visit Brookes and observe his Olympian games. By now, Brookes was 81 and his games were a well-established fixture. The 27-year-old De Coubertin was impressed and happy to learn from an elder who had put into action an event that correlated with his own vision. De Coubertin noted Brookes encouraged participation by common men and discouraged any form of professionalism. The two men, with their shared desire to have an International Competition in Athens, became fast friends.

In the summer of 1894, De Coubertin convened an international meeting in Paris to drum up international support for his dream of a revival of the Ancient Olympic games. While ill health prevented Dr. Penny Brookes from attending this conference, the participants decided to cooperate with the goal of holding the first modern Olympics in Athens in 1896. Unfortunately, Brookes never live to see his dream become reality. He died a few months before the opening ceremony.

De Coubertin got the games going and stood at the forefront during the difficult first 30 years. He faced numerous challenges including World War I and laid down a foundation that has allowed the Games to continue for over 100 years. He stepped down from the Presidency of the International Olympic Committee (IOC) in 1924 but remained honorary president until his death in 1937. His body is buried in Lausanne, Switzerland, the home of the IOC, but his heart was buried beneath a monument near the site of ancient Olympia.

So, to answer the question, “Who’s your daddy?” We vote with the IOC and award the Gold Medal to De Coubertin. We recommend duplicate Silver Medals to Zappas and Brookes.

As to the secondary question: "When did the first Modern Olympic Games take place?" 
1859 – Athens: Zappas’ Games.
1866 – London: Brookes’ Games.
1896 – Athens: De Coubertin’s Games.

Again, we go with De Coubertin and his 1896 games. The 1896 games were truly International and they kicked off an ongoing, continuous series of Olympic Games that continue to this current day with the 2008 Beijing Summer Games. 

If you wish to increase your knowledge, and see other viewpoints, please check out:

http://www.wenlock-olympian-society.org.uk/
http://www.zappas.org/
http://www.olympic.org/uk/