The flag of Portugal is a 2:3 green and red rectangle divided vertically into green at the hoist (2/5 of the flag’s length) and red at the fly (3/5). Centered in this partition a coat of arms consisting of an armillary sphere charged with the traditional Portuguese shield. It was officially adopted on June 30, 1911, but had in fact been in use since the Republican revolution of 5 October 1910.

Meaning of the Flag

Colours
The flag probably has a much more ambiguous meaning than the traditional, most popular explanations for its design. The most commonly held belief is that during the Estado Novo, the nationalist authoritarian regime, which lasted from 1933 until the 1974 Carnation Revolution, claims that the green represented hope and the red represented the blood of those who died serving the nation. This definition of the colours is currently the commonly accepted one, however the original meaning could be much more uncertain.

Some other theories claim that red represents the sunrise and sunset over the Portuguese ships during the Age of Exploration in the 16th century and the green represents the colour of the oceans which were sailed by the great Portuguese navigators. Other less nationalists theories allege that the green and red are the traditional colours of Iberic Federalism, a Republican-Socialist ideology very common at the beginning of the 20th century and which defended the political union of Portugal and Spain.

Portuguese shield
The traditional Portuguese shield (escudo) is present in almost every single Portuguese flag. And it is the prime Portuguese symbol, and as well as one of the oldest national symbols still used in the world and certainly one of the oldest in Europe. Used for more than 800 years, appears on all the Portuguese flags, except the first one. But the shield is in fact an evolution whose roots are in the first flag (1143-1185) and first king of Portugal.

The five white points in the five shields in the centre of the flag refer to a legend concerning the first King of Portugal, King Afonso Henriques or Afonso I. The story tells that before the Battle of Ourique (26 July 1139), King Afonso I was praying for the protection of the Portuguese people when a vision of Jesus on the cross appeared to him. King Afonso won the battle and, in gratitude, incorporated Christ's five wounds into his flag. This is said to be a myth, very similar to what occurred with the Roman Emperor Constantine. Some suggest this was done in order to get the Holy See recognize the Portuguese king. Still others claim the shields represent the five Moorish kings defeated in the Battle of Ourique.

The castles, which originally numbered nine, are a symbol of the Portuguese's victories over their enemies under King Afonso III's command. They could also relate to the nine Moorish castles defeated by Portugal in 1249; additionally, the castle was the symbol of the Kingdom of Algarve, the last one conquered by the Portuguese, when the definitive borders have been settled. Later, King John II reduced the number of castles in the flag down to seven.

Armillary sphere
The circular design is an armillary sphere which replaced the crown in the old monarchist flag. It represented the Portuguese Colonial Empire at the time of the Revolution as well as the discoveries of Portuguese explorers throughout the world. It was the symbol of King Manuel I (1495-1521), the "fortunate king", who ruled during the time period generally regarded as the peak of Portuguese power. Also, lending to the sphere's significance, the sphere was commonly used in town and city pillories.

The sphere was initially emblazened onto the flag by John VI (1816-1826) as a symbol of the kingdom of Brazil when he declared Brazil a kingdom under the United Kingdom of Portugal, Brazil and the Algarve. It was removed after the king's death, due to Brazil gaining its independence during his reign. The removal of the sphere was actually a request in the king's will, rather his son Pedro I's doing (a common misconception), in order to keep the territory in the family.

Evolution of the Portuguese Flag

1095 - 1139/1143

1139/1143 - 1185

The first Portuguese flag was used by the first king of Portugal in his shield during the battles. It was a blue cross under a white background, these were also the symbols of his father, Count Henry of Portugal (1093-1112), although his father's background colour was silver.

This flag is the origin of the blue and white colours in the centre of the Portuguese shield.

1185 - 1245/1248

1185 (1:1)The Royal arms were composed by five little shields (the escudetes) in a silver field, disposed in a cross, and pointing to the centre. The five shields represent the five wounds that King Alfonso I got in the Battle of Ourique or the five Moorish Kings defeated in that battle or even the five wounds of Christ.

This is a derivation of the first flag: the blue cross was transformed into five blue shields.

More recent flags

1245/1248 - 1385	1385 - 1485
1485 - 1495	1495 - 1521
1521 - 1578	1578 - 1640
1580 - 1640	1640 - 1667
1667 - 1707	1707 - 1816
1816 - 1826	1826 - 1830/1834
1830 - 1910	1910