Nope, not really. The Portuguese coat of arms is one of the oldest national symbols in Europe. It is a shield of smaller blue shields framed by castles and a globe. But the flag is a century old. Well, almost...
When D. Afonso Henriques inherited his fathers title of Count of Portucale he took the Cross of Burgundy as his symbol, as his father was from Burgundy. D. Afonso Henriques and his small army defeated the armies of five Caliphs at the Battle of Ourique, but popular belief is that the battle took place not in Ourique in the Alentejo, but in nearby Castro Verde. The Remedios Church there is filled with historical paintings of the battle, and at the Royal Basilica there are azulejo panels that tell the story of the mythical victory. Modern historians say both towns are too far south to make sense, and some place the real battle at Alfafar.
Soon after the Battle of Ourique, the new Portuguese coat of arms showed five small shields, which according to some represent the five defeated Moorish kings, but others claim it was the five wounds of Christ, with the six small bezants in each escutcheon of the 30 pieces of silver used to betray Christ. Four hundred years later the "coins" in each Quina would be reduced to five, adding up to 25, but the theory says to add the middle shield twice.
A change to the coat of arms came under Afonso III 1201-1279, who added a border of castles. Some say the arms of Castile inspired this, but many argue the castles are actually the towns of Mertola, Cacela, Tavira, Faro and Portimao and are the last five Moorish strongholds to fall. The Algarve was Portuguese in 1249, and a treaty in 1267 with Castile, solidified Portugals modern borders. The number of castles has strangely varied over the centuries, and was fixed at seven in the 15th century.
From the beginning, the colors of the nation had been blue and white, but in 1910, when Portugal's last king was deposed and the First Republic installed, the blue and white were replaced by green and red. It was said that the green symbolizes either hope or the green fields of Portugal, and red the effort or sacrifice of those who defend the nation. Nice make-over!