The Maria Theresa Thaler is probably one of the most famous coins in the world and is widely referred to as one of the most beautiful. Named after the Empress Maria Theresa, the ruler of Austria, Hungary and Bohemia between 1740 and 1780, the Maria Theresa Thaler is an Austrian silver bullion coin which has been minted continuously since 1741. All Thalers minted after 1780 carry the date '1780'. Thalers became the official trading coin throughout most German speaking countries. During the Second World War, it became the only currency in some countries. The obverse features a portrait of the Empress while the reverse shows the double-headed Hapsburg eagle.