http://books.google.at/books?id=iBKGXi1GpNkC&printsec=frontcover

The first known works on probability theory are these of Galileo and Pascal. In both cases it is notable that they where commissional work for wealthy gamblers. The autor argues that the investment of the gambling culture led to the establisment of this branch of mathematics.

The compulsive gamblers who spent hours studying the outcome of experimental trials with these pieces of apparatus [e.g. dices and decks of cards] were in effect scientists conducting a careful examination of the phenomenon of chance and randomness

He wonders why there is no knowledge of ancient greek lore in this field, since the greek and roman culture had a lot of fortune games such as dices.

The first unified theory - mainly a summary of the works of his prdecessors Gauss, Bernoulli and Pascal - was Laplace's A Philosopical Essay on Probabilities. A early social statistical method was developed by John Graunt in his Natural and Political Observations Made upon the Bills of Mortality