Manuscripts were still written and illuminated well into the sixteenth century, some dating to just before 1600. Many illuminators continued to work on various manuscripts, specifically the Book of Hours. The Book of Hours had been the most commonly produced manuscript from the 1450s onward, and was among the last manuscripts created. By the sixteenth century, however, manuscripts were mostly illuminated by artists retained by nobles or royals. Their work was required (and manuscripts were created) only for unusual occasions, such as noble or royal births, weddings, or other extraordinary occurrences. The number of copyists had greatly declined, as these types of manuscripts were not intended for mass, or even student, consumption.