Madeira is a fortified wine made on the Portuguese island of Madeira, in the North Atlantic Ocean. Madeira is produced in a variety of styles ranging from dry wines, which can be consumed on their own, as an apéritif, to sweet wines usually consumed with dessert. Cheaper cooking versions are often flavoured with salt and pepper for use in cooking, but these are not fit for consumption as a beverage.

The islands of Madeira have a long winemaking history, dating back to the Age of Exploration (approximately from the end of the 15th century), when Madeira was a standard port of call for ships heading to the New World or East Indies. To prevent the wine from spoiling, the local vintners began adding neutral grape spirits. On the long sea voyages, the wine would be exposed to excessive heat and movement, which benefited its flavour. This was discovered when an unsold shipment of wine was returned to the islands after a round trip.^{[citation needed]}

Today, Madeira is noted for its unique winemaking process that involves oxidizing the wine through heat and ageing. The younger blends (three and five years old) are produced with the aid of artificial application of heat to accelerate the aging process; the older blends, colheitas and frasqueiras, are produced by the canteiro method. Because of the way these wines are aged, they are very long-lived in the bottle, and those produced by the canteiro method will survive for decades and even centuries, even after being opened. Wines that have been in barrels for many decades are often removed and stored in demijohns where they may remain unharmed indefinitely.

Some wines produced in small quantities in Crimea, California, and Texas are also referred to as "Madeira" or "Madera"; however, most countries conform to the EU PDO regulations and limit the use of the term Madeira or Madère to wines that come from the Madeira Islands.

The roots of Madeira's wine industry date back to the Age of Exploration, when Madeira was a regular port of call for ships travelling to the East Indies. By the 16th century, records indicate that a well-established wine industry on the island supplied these ships with wine for the long voyages across the sea. The earliest examples of Madeira were unfortified and tended to spoil before reaching their destination. However, following the example of port, a small amount of distilled alcohol made from cane sugar was added to stabilize the wine by boosting the alcohol content. (The modern process of fortification using brandy did not become widespread until the 18th century.) The Dutch East India Company became a regular customer, picking up large, 423-litre (112 US gal) casks of wine known as "pipes" for their voyages to India.

The intense heat in the holds of the ships had a transforming effect on the wine, as discovered by Madeira producers when one shipment was returned to the island after a long trip. The customer was found to prefer the taste of this style of wine, and Madeira labeled as vinho da roda (wines that have made a round trip) became very popular. Madeira producers found that aging the wine on long sea voyages was very costly, so they began to develop methods on the island to produce the same aged and heated style. They began storing the wines on trestles at the winery or in special rooms known as estufas, where the heat of the island sun would age the wine.

With the increase of commercial treaties with England such as the Marriage Treaty in 1662, important English merchants settled on the island and, ultimately, controlled the increasingly important island wine trade. The English traders settled in the Funchal as of the seventeenth century, consolidating the markets from North America, the West Indies and England itself. Notable brands include Cossart and Gordon founded in 1745 and Blandy's in 1811.

The eighteenth century was the "golden age" for Madeira. The wine's popularity extended from the American colonies and Brazil in the New World to Great Britain, Russia, and Northern Africa. The American colonies, in particular, were enthusiastic customers, consuming as much as 95% of all wine produced on the island each year.