Sapphire, ruby and diamond neck badge of the Order of the Golden Fleece, early 20th century

Ferdinand I, Tsar of Bulgaria (1861-1948) was granted knighthood of the Austrian Order of the Golden Fleece in 1911. 

The Order of the Golden Fleece was founded in 1430 by Philip The Good, Duke of Burgundy (1396-1467) at Bruges to mark his marriage to Princess Isabella of Portugal (1397-1471). The aim of the Order was to protect the Christian Faith and hold its members to chivalric principles. 

The Ducal family of Burgundy was a cadet branch of the French Valois dynasty which had amassed an empire of personal union stretching from the Low Countries to Switzerland. Though its sovereignty was technically subservient to both the French crown and the Holy Roman Empire in its respective territories, the Burgundian dynasty sought to establish a strong independent realm between these two powers. Founding the highly prestigious Order of the Golden Fleece furthermore had as an advantage to bind the knights to the Duke of Burgundy and increase the diplomatic standing of the latter. 

When the last Burgundian Duke Charles the Bold passed away in 1477, his son-in-law Holy Roman Emperor Maximilian I (1459-1519) inherited the Low Countries as well as the position of Grand Master of the Order of the Golden Fleece. For centuries, the head of the House of Habsburg commanded the Order. When the Spanish Habsburg line became extinct in 1700, the order split into a Spanish and an Austrian branch since the first Spanish Bourbon King Philip V (1683-1746) continued to award the Order of the Golden Fleece as the highest Spanish chivalric order.

The Order’s motto is Pretium Laborum Non Vile Non Aliud (reward for work is not dishonourable). This motto is usually engraved on the neck badge of the Order which is constituted of a lamb skin supported by firesteels, the suspension is of B-shape in reference to Burgundy. The lamb skin refers to the Greek mythical story of Jason and the Argonauts. Next to the neck badge, knights receive a collar which remains property of the Order. The number of knights of the Austrian Order of the Golden Fleece is limited to fifty, each member is required to adhere to the Catholic Faith and to be born into the higher nobility.