Replica of Ercker's Prague ducat standard

Rudolf II Habsburg was the oldest son of emperor and king Maxmilian II and his cousin Maria. The matrimonial policy of the Habsburgs helped them conquer Burgundy, Spain, Portugal, Bohemia and Hungary. Later on they concentrated on keeping power in these countries with the help of mutual marriages of members of the Spanish and Austrian sides of the Habsburg family. Dire consequences of these marriages soon surfaced and were manifested by various degenerative signs including serious illnesses. Rudolf II is the best known ruling member of the Habsburg House whose health was worst affected by the family dispositions. Rudolf II was brought up in Spain, he never married but had several illegitimate children. His health problems worsened with age and he gradually withdrew from the world into his private interests, in particular sciences, art and collecting.

His ambitious younger brother Matthias II gradually deprived him of control over all family possessions. He died on January 20, 1612 at the Prague Castle where he is also buried.

Prague mintmaster Lazar Ercker (1583–1594) constantly had to tackle lack of precious metals by buying “used metal“, i.e. metal that was already processed once. He wrote a book on ores and the art of their smelting and testing. After his death, his wife Zuzana Erckerova led the Prague Mint for six years (1594–1600).