<P> These reformed calendars generally remained in use until the fifth or sixth century . Around that time most of them were replaced as civil calendars by the Julian calendar, but with a year starting in September to reflect the year of the indiction cycle . </P> <P> The Julian calendar spread beyond the borders of the Roman Empire through its use as the Christian liturgical calendar . When a people or a country was converted to Christianity, they generally also adopted the Christian calendar of the church responsible for conversion . Thus, Christian Nubia and Ethiopia adopted the Alexandrian calendar, while Christian Europe adopted the Julian calendar, in either the Catholic or Orthodox variant . Starting in the 16th century, European settlements in the Americas and elsewhere likewise inherited the Julian calendar of the mother country, until they adopted the Gregorian reform . The last country to adopt the Julian calendar was the Ottoman Empire, which used it for financial purposes for some time under the name Rumi calendar and dropped the "escape years" which tied it to Muslim chronology in 1840 . </P> <P> Although the new calendar was much simpler than the pre-Julian calendar, the pontifices initially added a leap day every three years, instead of every four . There are accounts of this in Solinus, Pliny, Ammianus, Suetonius, and Censorinus . </P> <P> Macrobius gives the following account of the introduction of the Julian calendar: </P>

What significant event each year is calculated off the julian calendar