Historical and current

In the 17th and 18th century, the use of silver Spanish dollars or "pieces of eight" spread from the Spanish territories in the Americas westwards to Asia and eastwards to Europe forming the first ever worldwide currency. Spain's political supremacy on the world stage, the importance of Spanish commercial routes across the Atlantic and the Pacific, and the coin's quality and purity of silver helped it become internationally accepted for over two centuries. It was legal tender in Spain's Pacific territories of the Philippines, Micronesia, Guam and the Caroline Islands and later in China and other Southeast Asian countries until the mid-19th century. In the Americas it was legal tender in all of South and Central America (except Brazil) as well as in the U.S. and Canada until the mid-19th century. In Europe the Spanish dollar was legal tender in the Iberian Peninsula, in most of Italy including: Milan, the Kingdom of Naples, Sicily and Sardinia, as well as in the Franche-Comté (France), and in the Spanish Netherlands. It was also used in other European states including the Austrian Habsburg territories.

There are other coins/currencies that have been used over the centuries. The Austrian Maria Theresa thaler is still used in some back areas of the Middle East and Africa and was first issued in 1741. There was also the Roman Denarius, which for hundreds of years was the world's premier currency.[citation needed]