For general access to the Wolfram Knowledgebase, use entities of type HistoricalPeriod instead of HistoricalPeriodData.


gives the value of the specified property for the historical period entity.


gives a list of property values for the specified historical period entities.


gives the specified annotation associated with the given property.


  • HistoricalPeriodData[] gives a list of all historical period entities.
  • HistoricalPeriodData["Properties"] gives a list of available properties.
  • The specified entity in HistoricalPeriodData can be an Entity, EntityClass, entity canonical name, or list thereof.
  • The specified property can be an EntityProperty, EntityPropertyClass, property canonical name, or list of properties.
  • Properties that do not apply or are not known in a particular case are indicated by Missing[].
  • Properties include:
  • "CountriesInvolved"areas involved
    "EndDate"end date
    "PeopleInvolved"people involved
    "StartDate"start date
  • Some properties are available for HistoricalPeriodData as a whole and can be given using the form HistoricalPeriodData[property]. Such properties include:
  • "Entities"all available entities
    "EntityCount"total number of available entities
    "Classes"all available entity classes
    "EntityClassCount"total number of available entity classes
    "SampleEntities"list of sample entities
    "SampleEntityClasses"list of sample entity classes
    "EntityCanonicalNames"list of all entity canonical names
    "PropertyCanonicalNames"list of all property canonical names
    "EntityClassCanonicalNames"list of all entity class canonical names
    "RandomEntities"pseudorandom sample entities
    {"RandomEntities",n}n pseudorandom entities
    "RandomEntityClasses"pseudorandom sample entity classes
    {"RandomEntityClasses",n}n pseudorandom entity classes
  • The following annotations can be used in the third argument of HistoricalPeriodData[entity,property,annotation]:
  • "Qualifiers"the list of possible qualifiers for the property
    "QualifierValues"the list of possible values that can be given to each qualifier
    "DefaultQualifierValues"the list of default values for the property's qualifiers
    "Description"a brief textual description of the property
    "Definition"a detailed textual definition of the property
    "Source"source information for the property
    "Date"the date associated with the entity-property value (if any)
    "PhysicalQuantity"the physical quantity associated with the entity-property value
    "Unit"the unit associated with the entity-property value
    "EntityAssociation"an association of entities and entity-property values
    "PropertyAssociation"an association of properties and entity-property values
  • If a function is provided as an annotation, it will be used to aggregate the result data. Typical aggregation functions include:
  • Minthe minimum value
    Maxthe maximum value
    Meanthe mean value
    Commonestthe most frequently occurring value
    Medianthe median value
    Totalreturns the total
    Lengththe number of elements


open allclose all

Basic Examples  (3)

Use for entity discovery:

Get a list of sample entities for historical periods:

Find a property of a historical period:

Neat Examples  (1)

Create a timeline of sample historical periods in the Common Era:

Wolfram Research (2014), HistoricalPeriodData, Wolfram Language function, https://reference.wolfram.com/language/ref/HistoricalPeriodData.html.


Wolfram Research (2014), HistoricalPeriodData, Wolfram Language function, https://reference.wolfram.com/language/ref/HistoricalPeriodData.html.


Wolfram Language. 2014. "HistoricalPeriodData." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/HistoricalPeriodData.html.


Wolfram Language. (2014). HistoricalPeriodData. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/HistoricalPeriodData.html


@misc{reference.wolfram_2024_historicalperioddata, author="Wolfram Research", title="{HistoricalPeriodData}", year="2014", howpublished="\url{https://reference.wolfram.com/language/ref/HistoricalPeriodData.html}", note=[Accessed: 30-May-2024 ]}


@online{reference.wolfram_2024_historicalperioddata, organization={Wolfram Research}, title={HistoricalPeriodData}, year={2014}, url={https://reference.wolfram.com/language/ref/HistoricalPeriodData.html}, note=[Accessed: 30-May-2024 ]}