Due to the importance of its position on the world map this province has been invaded and fought over by the Phoenicians, Romans and Moors. Closely associated with the sea throughout its history this was the base of the famous Henry the Navigator who, from the point at Sagres organized the successful 15th Century exploration of the New World.

The Algarve has been inhabited for thousands of years but the first developed society was probably the Phoenicians in 1.100 BC and then followed by the Tartessus tribe to about 600 BC. In the same century there is also evidence of a tribe by the name of "Conii" being found around the area of Vila Real de Santo António followed by another tribe named "Turduli" in the same area in 400 BC. In between these two tribes the whole area had been inhabited by a wave of Celts. Another tribe from this same period was the "Cynetes".

Somewhere around 235 BC the Romans moved up from their base in Cadiz to occupy the Algarve and were eventually removed by the invading Visigoths in about 410 AD. here they were to stay until 711 when the Omayyads from North Africa took possession of the southern Iberian Peninsular. The Moors were to stay in possession of the Algarve until 1185 when Sancho I and his Christian army briefly captured most towns with Silves holding out to 1189. However, by 1191 the Moors had these same towns back in their possession. Finally, King Sancho II and his Christian army helped by Crusaders retook the Algarve in 1236. The first time that the Algarve was referred to as a part of the Kingdom was when Afonso III was crowned in 1249 he took the title of "King of Portugal and all Algarve". However, it was not until 1272 that Afonso III eventually took Faro which was the last stronghold of the Moors in the Algarve.

The King of Castile did not at first accept Afonso III's claim to the Algarve and it was only in 1267 at the Treaty of Badajoz that this situation was temporarily resolved. The situation was again settled in 1297 at the Treaty of Alcañices when the actual boundaries between the two countries was agreed. The Algarve inhabitants remained for nearly 300 hundred years without any further change in their rulers but subject to raids from pirates. This situation changed when the throne of Portugal fell vacant in 1580 and the nearest relative in line was King Felipe II of Spain who soon crowned himself as King of Portugal.

Shortly after this the Algarve fell prone to attacks from passing English vessels. In 1596 the Earl of Essex invaded Faro and removed amongst other things the historic library belonging to the Bishop of Faro. Francis Drake failed in his attack on Lagos in 1597 so he landed in Sagres and destroyed the house in which Henry the Navigator had lived.

In 1640 the Portuguese decided to rid themselves of their disliked absent ruler and successfully reclaimed their Kingdom placing João IV, (Duque de Bragança), on their throne.

The Algarve nearly became a separate Kingdom when the ambitious prime minister of Carlos IV of Spain, Manuel Godoy, was involved in the Treaty of Fontainebleau in 1807. In the agreement between Emperor Napoleon and Carlos IV it was agreed that Portugal would be carved into areas to be governed by France and Spain, Manuel Godoy to assume the Algarve. However, the Wars that followed between Portugal supported by England and Spain and France proved a failure for Napoleon and his plans.

The Algarve was also to play a part in the problems once more caused by the claims to the throne of Portugal in 1822. Two royal brothers, Pedro and Miguel, warred against each other with liberal minded Pedro winning against the hardliner Miguel. The Algarve towns, as in most of the country, were at the time divided in their support and from Estombar appeared a Miguel supporter named "Remexido" with a strong band of followers. His support for Miguel was brutally applied to his enemies and extending especially to robbery. In 1833 Pedro had to send some 2.500 men to the Algarve to successfully capture this elusive and troublesome bandit.