Editing Roman calendar (section)

===Later reforms===
{{main|Byzantine calendar}}
After [[Assassination of Julius Caesar|Caesar's assassination]], [[Mark Antony]] had Caesar's birth month Quintilis renamed [[July (month)|July]] (''{{lang|la|Iulius}}'') in his honor. After Antony's [[Battle of Actium|defeat at Actium]], [[Augustus]] assumed control of Rome and, finding the priests had (owing to their inclusive counting) been intercalating every third year instead of every fourth, suspended the addition of leap days to the calendar for one or two decades until its proper position had been restored. See [[Julian calendar#Leap year error|Julian calendar: Leap year error]]. In 8 BC, the [[plebiscite]] ''Lex Pacuvia de Mense Augusto'' renamed Sextilis [[August (month)|August]] (''{{lang|la|Augustus}}'') in his honor.{{sfnp|Rotondi|1912|p=441}}{{sfn|Macrobius|loc=Book I, Ch. 12}}{{sfnp|Kaster|2011}}{{efn|There are some documents which state the month had been renamed as early as 26 or 23 BC, but the date of the Lex Pacuvia is certain.}}

In large part, this calendar continued unchanged under the [[Roman Empire]]. ([[Roman Egypt|Egypt]]ians used the related [[Alexandrian calendar]], which Augustus had adapted from [[Egyptian calendar|their wandering ancient calendar]] to maintain its alignment with Rome's.) A few emperors altered the names of the months after themselves or their family, but such changes were abandoned by their successors. [[Diocletian]] began the 15-year [[indiction]] cycles beginning from the AD 297 census;<ref name=matlock/> these became the required format for official dating under [[Justinian I|Justinian]]. [[Constantine the Great|Constantine]] formally established the 7-day [[week]] by making [[Sunday]] an official holiday in 321.{{Citation needed|date=November 2019}} Consular dating became obsolete following the abandonment of appointing nonimperial consuls in AD 541.<ref name=matlock/> The Roman method of numbering the days of the month never became widespread in the Hellenized eastern provinces and was eventually abandoned by the [[Byzantine Empire]] in [[Byzantine calendar|its calendar]].

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