Maximilian II, Holy Roman Emperor
In 1560 Crato was called to the imperial court in Vienna to become personal physician to Emperor [[Ferdinand I, Holy Roman Emperor|Ferdinand I]]. As the emperor's health declined, Crato resettled to Vienna; however, he and his family returned to Breslau after Emperor Ferdinand died in 1564. In the next year, however, he was named principal personal physician of Emperor [[Maximilian II, Holy Roman Emperor|Maximilian II]], whom he served for 11 years.