Port is born (1500-1700)
By the 1600's, the wine-trade dramatically surged with England as political tensions between England and France led the English government to increase the cost of duty on French imports. This led to greater attention being payed to the wines from Portugal's hilly Douro Valley which were naturally heavier and of a fuller body than other Portuguese wines, and thus more similar to the French wines that the English consumer had grown accustomed to.
Due the complications of shipping these wines by land through the rugged terrain of northern Portugal, shipments of Douro Valley wines reached Porto by the river itself. They were stored in Port wine cellars on the Douro before being transported on unique flat-bottom boats known as 'rabelos'. The long sea voyage to England further required some ingenuity in order for the precious cargo to arrive unspoiled. To fortify it against the rigors of sea, brandy was at times added to Portuguese wine before it had finished fermenting. Although this process is similar to the common method of production of Port, the addition of brandy was not as integral to process of making Port wine as it is today. In fact, it wouldn't be until the 18th century when the addition of a fortifying spirit became a definitive feature in this kind of wine.
Modern port wine arrives (1700 - 21st Century)
The years between the mid-18th and early-19th centuries were arguably the most important for the establishing of modern Port. For starters, in 1756, during the rule of the Marquis of Pombal, the Douro Valley became just the third protected wine region in the world. Along with setting an official standard for the wines produced in the region, this also secured a Portugal as steady exporter of wine. The increased demand for Port meant more barrels of wine having to be stored in Porto before being shipped overseas. As a result, the fortification technique became more and more necessary for the business of port wine. And while it did help with the storage of Port both at home and while at sea, it should also be noted that by this time the sweeter and heavier fortified wines making their way down the Douro had become highly regarded and in many cases preferred for their rich aromatic flavors, especially by the English.
Today, it would be hard to think of Portuguese wine without Port coming to mind. Shaped by the land, economy and its history, Port wine is truly synonymous with Portugal. And thanks to the decrees of the Marquis of Pombal, it is a treat which will be produced along the sun-drenched shores of the Douro River for many more years to come.