"Long before the times that history remembers, there was an age of great magic in an anciet land called Kiltia. When the great glood swept over the world, the culture perished, but a key to its magic and secrets -- a book called the Grand Grimoire -- is said to have survived. It it foretold that the one who holds the ancient text will be be able to change the world. Many have sought the book, but none have ever found it. Though the ages, many legends were written about the Grand Grimoire, but legends are often forgotten. Those who once knew it called it... The Final Fantasy. One day in the peaceful, snow-covered town of St. Ivalice, a young boy named Mewt discoveres a mysterious book with no title in the local bookstore. Little do Mewt and friends Marche and Ritz realize that they will soon begin the greatest adventure of their lives."

Taken from the official strategy guide. Do more research. :P