The bear ring (or bear garden) was a ground for the blood-sport of bear baiting, popular during Elizabethan times. It would consist of a pit, in which a bear would be chained by the neck or leg to a pole in the middle, and banks of raised seating for the spectators. A pack of hunting dogs would be released to fight the bear, and bets would be placed on which would win. The main bear ring in London was the Paris Garden at Southwark.
Holy Roman Emperor Rudolf II was King of Hungary and Croatia, King of Bohemia, and Archduke of Austria. He was a great patron of arts and the occult sciences. Although a Catholic, he was tolerant of Protestantism, Judaism and other religions. His determination not to take sides caused political chaos. However, his tolerance did not extend to the Ottoman Turks, with whom he started a long and exhausting war. Eventually, in 1611 Rudolf was forced to abandon the throne in favour of his brother.
An annotated copy of Erasmus belonging to Bruno was indeed found in the privy at the monastery in Naples. This was one of the crimes against the faith for which he was accused of heresy.
What is being described here is jousting, a competition in which two knights charged at each other on horseback with blunt lances. Different amounts of points were given for breaking the lance on the opponent’s chest or head, causing the opponent to drop his lance, or knocking him from his horse. Only nobles were allowed to compete in the tournaments. They usually dressed their horses and stewards in bright colours with their own heraldic badge; competing in the tournament was a mark of bravery and winning was a huge honour. The tournaments could be very dangerous, with many knights gaining injuries or even losing their lives, but a large amount of prize money was at stake. Jousting was very popular from the medieval period to the 17th century, with large crowds gathering to watch.
Below are two videos showing jousting. The first is a historical event at the Tower of London. The second is a real modern jousting Tournament.