The terms anno Domini (AD) and before Christ (BC) are used when designating years in the Gregorian and Julian calendars. The term anno Domini is Medieval Latin and means "in the year of the Lord" but is often presented using "our Lord" instead of "the Lord", taken from the full original phrase "anno Domini nostri Jesu Christi", which translates to "in the year of our Lord Jesus Christ". The form "BC" is specific to English, and equivalent abbreviations are used in other languages: the Latin form, rarely used in English, is ante Christum natum (ACN) or ante Christum (AC).
AD 4 was a common year starting on Wednesday or a leap year starting on Tuesday of the Julian calendar and a leap year starting on Tuesday of the Proleptic Julian calendar. In the Roman Empire, it was known as the Year of the Consulship of Catus and Saturninus. The denomination "AD 4" for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
The 0s BC is the period between 9 BC and 1 BC, the last nine years of the before Christ era. It is one of two "0-to-9" decade-like timespans that contain nine years, along with the 0s.
The proleptic Julian calendar is produced by extending the Julian calendar backwards to dates preceding AD 8 when the quadrennial leap year stabilized. The leap years that were actually observed between the implementation of the Julian calendar in 45 BC and AD 8 were erratic.
Year 1 BC was a common year starting on Friday or Saturday in the Julian calendar and a leap year starting on Thursday in the proleptic Julian calendar. It was also a leap year starting on Saturday in the Proleptic Gregorian calendar. At the time, it was known as the Year of the Consulship of Lentulus and Piso. The denomination 1 BC for this year has been used since the early medieval period when the Anno Domini calendar era became the prevalent method in Europe for naming years. The following year is AD 1 in the widely used Julian calendar and the proleptic Gregorian calendar, which both do not have a "year zero".
Year 45 BC was either a common year starting on Thursday, Friday or Saturday or a leap year starting on Friday or Saturday and the first year of the Julian calendar and a leap year starting on Friday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Caesar without Colleague. The denomination 45 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Year 54 BC was a year of the pre-Julian Roman calendar. At the time, it was known as the Year of the Consulship of Appius and Ahenobarbus. The denomination 54 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Year 38 BC was either a common year starting on Sunday or Monday or a leap year starting on Saturday, Sunday or Monday of the Julian calendar and a common year starting on Sunday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Pulcher and Flaccus. The denomination 38 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. It was also the first year of the Spanish era calendar in use in Hispania until the 15th century.
Year 41 BC was either a common year starting on Wednesday or Thursday or a leap year starting on Tuesday, Wednesday or Thursday of the Julian calendar and a leap year starting on Wednesday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Antonius and Vatia. The denomination 41 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Year 34 BC was either a common year starting on Friday, Saturday or Sunday or a leap year starting on Friday or Saturday of the Julian calendar and a common year starting on Friday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Antonius and Libo. The denomination 34 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Year 30 BC was either a common year starting on Wednesday, Thursday or Friday or a leap year starting on Thursday of the Julian calendar and a common year starting on Wednesday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Octavian and Crassus. The denomination 30 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Year 26 BC was either a common year starting on Tuesday or Wednesday or a leap year starting on Monday, Tuesday or Wednesday of the Julian calendar and a common year starting on Monday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Augustus and Taurus. The denomination 26 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Year 20 BC was either a common year starting on Wednesday or Thursday or a leap year starting on Tuesday, Wednesday or Thursday of the Julian calendar and a common year starting on Tuesday of the Proleptic Julian calendar. At the time, it was also known as the Year of the Consulship of Appuleius and Nerva. The denomination 20 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Year 17 BC was either a common year starting on Sunday or Monday or a leap year starting on Saturday, Sunday or Monday of the Julian calendar and a leap year starting on Friday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Furnius and Silanus. The denomination 17 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Dionysius Exiguus was a 6th-century Eastern Roman monk born in Scythia Minor. He was a member of a community of Scythian monks concentrated in Tomis, the major city of Scythia Minor. Dionysius is best known as the inventor of Anno Domini (AD) dating, which is used to number the years of both the Gregorian calendar and the (Christianised) Julian calendar. Almost all churches adopted his computus for the dates of Easter.
A calendar era is the period of time elapsed since one epoch of a calendar and, if it exists, before the next one. For example, the current year is numbered 2025 in the Gregorian calendar, which numbers its years in the Western Christian era.
Annianus of Alexandria was a monk and writer who flourished in Alexandria during the pontificate of Theophilus I around the beginning of the 5th century.
A year zero does not exist in the Anno Domini (AD) calendar year system commonly used to number years in the Gregorian calendar ; in this system, the year 1 BC is followed directly by year AD 1. However, there is a year zero in both the astronomical year numbering system, and the ISO 8601:2004 system, a data interchange standard for certain time and calendar information. There is also a year zero in most Buddhist and Hindu calendars.
The 0s began on January 1, AD 1 and ended on December 31, AD 9, covering the first nine years of the Common Era. It is one of two "0-to-9" decade-like timespans that contain nine years, along with the 0s BC.
The 1st century would see the foundation of Christianity and the growth and establishment of Buddhism in China.
Map of the world in AD 1.
Map of the Eastern Hemisphere in AD 1.
Germanic tribes in Europe in AD 1:Settlements before 750 BCNew settlements after 750 BC until 1 ADNew settlements until 100 ADNew settlements after 100 AD
