Portuguese real

By the beginning of the reign of King Duarte I in 1433, the real branco (equivalent to 840 dinheiros) had become the unit of account in Portugal.

[3] Due to the historically low value of the real, large sums were usually expressed in milréis (or mil-réis) of 1,000 réis, a term that has been in use since at least the 1760s.

[5] The Napoleonic Wars of the early 19th century spawned the issue of the paper milréis which eventually depreciated versus the silver cruzado and the gold escudo.

It also changed the main unit of account from the real to the milréis (1$000)[6] with decimal subdivisions used in its coins.

After the Napoleonic Wars the Brazilian unit was devalued further, with the escudo rising to 2$500 in 1834 and 4$000 in 1846.

Coins and banknotes were also issued denominated in réis for use in the different parts of the Portuguese Empire.

[3] Portuguese influence in the Persian Gulf, especially in Portuguese Oman extended the use of the term "real", though not the actual currency or value, to the Middle East and the slightly Arabicized form of the word "real", the "riyal" is the currency of The Kingdom of Saudi Arabia and the current (but soon to be former currency in favor of the toman) of Iran.

[7] Before the middle of the 19th century, many different denominations were minted, often with values in terms of the real which increased over time.

For example, the cruzado was introduced at a value of 324 real branco in the reign of King João II.

It was fixed at a value of 400 réis during King João III's reign and this remained the value of the silver cruzado until the reign of King Pedro II, when it was revalued to 480 réis.