Indiction An indiction is any of the years in a 15-year cycle used to date medieval documents . Each year was numbered : first indiction , second indiction , etc . However , the cycles were not numbered , thus other information is needed to identify the specific year . Indictions originally referred to an agricultural or land tax in late third-century Roman Egypt . These were originally in 5-year cycles beginning in 287 , then in a non-cyclic series which reached number 26 by 318 . But by 314 the 15-year cycle had appeared . The Chronicon Paschale ( c. 630 ) assigned its first year to 312 - 313 , whereas a Coptic document of 933 assigned its first year to 297 - 298 , one cycle earlier . Both of these were years of the Alexandrian calendar whose first day was Thoth 1 on August 29 in years preceding common Julian years and August 30 in years preceding leap years , hence each straddled two Julian years . The indiction was first used to date documents unrelated to tax collection in the mid- fourth century . By the late fourth century it was being used to date documents throughout the Mediterranean . In the Eastern Roman Empire outside of Egypt , the first day of its year was September 23 , the birthday of Augustus . During the last half of the fifth century , probably 462 , this shifted to September 1 , where it remained throughout the rest of the Byzantine Empire . But in the western Mediterranean , its first day was September 24 according to Bede , or the following January 1 , called the papal indiction . For the historical January 1 to December 31 year following September 1 , 23 , or 24 , add three to the Anno Domini year , then divide by 15 . The remainder is the indiction , but if the remainder is zero , then the indiction is 15 . References Yiannis E. Meimaris , Chronological systems in Roman-Byzantine Palestine and Arabia ( Athens , 1992 ) , 32-34 Chronicon paschale 284–628 AD , trans . Michael Whitby , Mary Whitby ( Liverpool , 1989 ) , 10 . Leo Depuydt , `` AD 297 as the beginning of the first indiction cycle '' , The bulletin of the American Society of Papyrologists , 24 ( 1987 ) : 137-9 . Roger S. Bagnall , K. A. Worp , The chronological systems of Byzantine Egypt ( Zutphen , 1978 ) . Bonnie Blackburn , Leofranc Holford-Strevens , The Oxford companion to the year ( Oxford , 1999 ) , 769-71 . V [ enance ] Grumel , `` Indiction '' , New Catholic encyclopedia . S. P. Scott [ Justinian I ] , `` Forty-seventh new constitution '' [ Novella 47 ] , The civil law [ Corpvs jvris civilis ] ( 1932 ; reprinted New York , 1973 ) , 16 ( in 7 ) : 213-15 .  This history article is a stub . You can help Wikipedia by expanding it . Categories : Calendars | History stubs In other languages : Български | Deutsch | 日本語 | Français 