The primary answer to your question is ahistorical in the sense that the reason why it is grapes rather than other fruits is biological. Grapes grow easily in lots of different climates and in soils that are poorly suited for other agricultural products. Furthermore grapes have the correct balance of acids and sugars to allow fermentation to occur and result in a pleasant product.

In terms of why grape based wines have spread to so many places that largely has to do with Christian missionaries bringing grapes to new settlements so that they would be able to ensure a stable amount of wine for sacramental purposes. There are many nations with very rich wine cultures whose original plantings are due to monastic orders such as Chile or Argentina.

Sources: The Oxford Encyclopedia of Wine.