I mentioned these briefly in 2012 when discussing papal bulls. Starting from the 6th century, popes used bulls to authenticate their decrees. Initially lumps of clay, they evolved to lead. Byzantine emperors took this a step further, making their seal out of gold, hence a chrysobull (from Greek chrysos, "gold"). The chrysobull carried by Boutoumites was an assurance that he represented the word of the emperor. (It worked, as you can read here.)
The Holy Roman Emperors liked the look of gold and the status it conferred on their decrees, as did the popes, so both they and other rulers sent out golden bulls for many occasions.
A Golden Bull of 1213 from the papacy to King John of England confirmed their alliance. A year later, Holy Roman Emperor Frederick II issued a Golden Bull ceding all territory north of the River Elbe to Denmark. One of the most famous was the Golden Bull of 1356, issued by Holy Roman Emperor Charles IV (he is mentioned here), declaring the constitutional structure of the Holy Roman Empire—an arrangement that would last the next 400 years.
Emperor Alexios had issued another Golden Bull in 1082, giving Venetian merchants tax-exempt trading rights, so long as their fleets defended the Adriatic Sea against the Normans. The Adriatic is on the east coast of Italy and was an access point for invaders from the east. Venice was at the extreme northern end, in an ideal location to police the whole area. Let's look at the Adriatic and its medieval history next time.
