Maria Theresa thaler

The Maria Theresa thaler (MTT) is a silver bullion coin that has been used in world trade continuously since they were first minted in 1741, at that time using the then Reichsthaler standard of 9 thalers to the Vienna mark. In 1750 the thaler was debased to 10 thalers to the Vienna Mark (a weight approximating half a pound of fine silver). The following year the new standard was effectively adopted across the German-speaking world when that standard was accepted formally in the Bavarian monetary convention. It is owing to the date of the Bavarian Monetary convention that many writers erroneously state that the Maria Theresa Thaler was first struck in 1751. It was named after Empress Maria Theresa, who ruled Austria, Hungary, and Bohemia from 1740 to 1780. The word thaler gave rise to daalder and daler, which became dollar in English.

Since 1780, the coin has always been dated 1780. On 19 September 1857, Emperor Francis Joseph of Austria declared the Maria Theresa Taler to be an official trade coinage. A little over a year later, on 31 October 1858, the Maria Theresa Taler lost its status as currency in Austria.

The MTT could also be found throughout the Arab world, especially in Saudi Arabia, Yemen and Muscat and Oman, and in India. During the Japanese occupation of Indonesia in World War II, enough people preferred it to the money issued by the occupying forces that the American Office of Strategic Services created counterfeit MTTs for use by resistance forces.

In German-speaking countries, following a spelling reform dated 1901 which took effect two years later, "Thaler" is written "Taler" (the spelling of given names like "Theresia" was not affected). Hence 20th-century references to this coin in German and Austrian sources are found under "Maria-Theresien-Taler". The spelling in English-speaking countries was not affected.

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