The city where the ruler spends most of their time. If there is more than one capital, supply all names and enclose in curly braces. Example: {Susa; Pasargadae; Persepolis; Ecbatana; Babylon}.

Note that the capital may differ from the largest city (see below). Capital may be difficult to code for archaeologically known societies. If there is reasonable basis to believe that the largest known settlement was the seat of the ruler, code it as the capital (and indicate uncertainty in the narrative paragraph).

Archaeologists can often recognize special architectural structures such as ceremonial centers, citadels, or palaces. These features can be confirmed after a thorough study of the region and settlement network.

If such an inference cannot be made, code as "unknown". (The largest settlement is coded elsewhere.)

• ‘quasi-polity’ = or ‘none’. Use if, for example, the NGA is inhabited by many politically independent groups. There are four types of quasi-polity: archaeological, temporal, complex, and dominant. See: Quasi-Polities: further information.



• ‘nominal’ = regional rulers pay only nominal allegiance to the overall ruler and maintain independence on all important aspects of governing, including taxation and warfare.
  Example: Japan during the Sengoku period.



• ‘loose’ = the central government exercises a certain degree of control, especially over military matters and international relations. Otherwise, regional rulers are left alone.
  Example: European “feudalism” after the collapse of the Carolingian Empire.



• ‘confederated state’ = regions enjoy a large degree of autonomy in internal (regional) government. Regional governors are either hereditary rulers, elected by elites, or elected by the population. Regions can levy and dispose of their own taxes. Use this category for more centralized “feudal states.”



• ‘unitary state’ = regional governors are appointed and removed by central authorities. Taxes are imposed by and transmitted to the center.

• alliance with: belongs to a long-term (>2 years) military-political alliance of independent polities. “Long-term” refers to a more or less permanent relationship extending over multiple years.



• personal union with: the polity is united with another (or others) through dynastic marriage, inheritance, or similar circumstances. The union is tied to the ruler personally and dissolves when they die or are displaced.



• nominal allegiance to: the polity pays formal allegiance (e.g., suzerainty) to another polity while maintaining political, military, and economic independence. Often corresponds to “nominal” under the degree of centralization of the dominant polity.



• vassal state of: the polity is politically, economically, and/or militarily dependent on another state. Includes vassalage, foreign military presence, or consistent external interference. May be part of a larger structure (e.g., Holy Roman Empire or South Asian mandala system).



• none: the polity is politically independent and not in any long-term alliance or personal union with another polity.

• continuity: continuity of culture and ethnicity. Examples: Roman Principate continues from Roman Republic; Hawaii III continues from Hawaii II.



• absorption: the current polity added the preceding polity to its territory (e.g., through conquest, treaty, or dynastic marriage). The elite and general population are not substantially replaced, though cultural assimilation may occur. Examples: Roman Republic absorbed La Tène C2-D; UK absorbed Scotland (1707).



• elite replacement: over 50% of the preceding elites were replaced by newcomers via conquest or migration. Also applies when external elites are introduced to previously egalitarian societies. Examples: Kassite Babylonia replaced Amorite elites; Orokaiva - Colonial introduced elites to Orokaiva - Precolonial. Note: Internal elite replacement via rebellion is usually coded as continuity.



• population replacement: over 50% of both elites and general population were replaced. Typically involves major language and cultural changes. Examples: Oneota replaced Cahokia - Sand Prairie; Yayoi period replaced Final Jomon in Japan.



• secession: the polity declares independence or breaks away from a predecessor polity. Applies both when the predecessor continues to exist (e.g., Ireland from UK) and when it disintegrates (e.g., Ukraine from USSR).



• territorial consolidation: the polity unifies a previous quasi-polity through conquest or integration. Applies only if the predecessor had no political unity. Examples: Northern Song unified Five Dynasties; Tokugawa Shogunate unified Azuchi-Momoyama Japan.

We are interested in cataloguing the relative stability of past societies as proxied by the transition of power from one ruler to the next. In particular, we identify each transition of power (from named predecessor to named successor) and record whether it took place through normal succession mechanisms (whether legal/institutionalized means or customary/de facto procedures) or as the result of a conflict.

We are seeking to record this information across the Seshat sample of polities, subject to availability of evidence. We are particularly interested in documenting the ebb and flow of stability in particular regions over time.

Coding Instructions

• Predecessor: If a ruler came to power after a period during which the polity had no ruler (e.g. an interregnum), enter “None” in the predecessor field.



• Successor: If a ruler’s reign was followed by a period during which there was no ruler, enter “None” in the successor field.



• Contested: Was the transition from predecessor to successor contested in any way? Code present if there was a contest at any time from the end of the predecessor’s reign to the end of the first 365 days of the successor’s reign.
  
  
  
  • This is a general variable covering many possibilities, disambiguated in other variables.
  
  
  • Also code present if the transition was contested in a way not covered by other variables (e.g. judiciary challenges election results).
  
  
  
  



• Overturn: Was the predecessor forcibly removed from power (e.g., assassination, forced abdication, or external invasion)?
  
  
  
  • Succession crises without clear lines of succession (e.g., Mamluk Sultanate) do not count as overturns but still count as contested transitions.
  
  
  • Examples include:
    
    
    
    1. The dynasty ends with no heir;
    
    
    2. A ruler dies and divides power, leading to civil war;
    
    
    3. No formal succession rules exist, and every transition involves conflict.
    
    
    
    
  
  
  
  



• Predecessor assassination: Was the predecessor assassinated? Applies to any killing, including judicial executions (e.g., Charles I of England).



• Intra-elite coup: Code present if either:
  
  
  
  • 1. The predecessor was removed by an elite-led coup, or
  
  
  • 2. The successor was challenged by rival elites during their first year.
  
  
  
  



• Military revolt: Like an intra-elite coup, but led by professional soldiers or officers (not noble retinues).



• Popular uprising: Rebellions where the majority of participants are non-elites.



• Separatist rebellion: A region attempts to secede from the polity, successfully or not.



• External invasion: Another polity invades. The invasion need not specifically aim to remove the ruler. Small skirmishes do not count.



• External interference: An external force aids internal rebels (e.g., with money or arms). Can co-occur with external invasion.

Instability Events

A significant historical event characterized by internal social, political, or economic turmoil.
This model captures key attributes of such events, including their types, intensity, extent, and reliability.

Event Types

• Assassination: Targeted killing of a political or social leader (not a private person) as a representative of a group or institution.


• Execution: Killing of an overthrown ruler or faction leader via (quasi)legal procedures.


• Coup d’état: Attempted overthrow by elites. Includes failed coups if deadly; includes military mutinies.


• Terrorism: Politically motivated attack by individuals or small groups against institutions or society. Example: medieval Order of Assassins.


• Urban Riot: Group-on-group violence within a city, often the capital.


• Rural Uprising: Localized violence involving commoners (e.g., peasants, slaves) against elites or the state.


• Separatist Rebellion: A region rebels with the goal of secession and independence. Can be successful or failed.


• Revolution: Overthrow of elites with mass participation and ideological goals (e.g., regime change, constitutional transformation).


• Civil War: Prolonged, large-scale violence involving multiple social classes across several provinces.

Note: Failed attempts count as valid events. Multiple types per event are allowed.

Extent

Geographic spread of violence across provinces, districts, or capital.
Provinces = major divisions; Districts = sub-provinces; Capital = polity capital only.

Extent Involvement (choose: 1, 2, 4, 6, 8, or 10)

• 1: Neighborhood or village


• 2: Small town or rural district


• 4: Single province


• 6: Polity capital or 2 provinces


• 8: Polity capital and 1–2 provinces


• 10: Polity capital and 3+ provinces

Intensity

Demographic severity measured by number of deaths.

Intensity Scale (choose: 0, 1, 2, 4, 6, 8, 10, or 12)

• 0: No deaths


• 1: One or few deaths


• 2: Tens killed


• 4: Hundreds killed


• 6: Thousands killed


• 8: Tens of thousands killed


• 10: Hundreds of thousands killed


• 12: Millions killed

We define Crises as arising within polities, which we define as an independent political unit. Kinds of polities range from villages (local communities) through simple and complex chiefdoms to states and empires.

A polity can be either centralized or not (e.g., organized as a confederation). What distinguishes a polity from other human groupings and organizations is that it is politically independent of any overarching authority; it possesses sovereignty.

Polities are defined spatially by the area enclosed within a boundary on the world map. There may be more than one such area. Polities are dynamical entities, and thus their geographical extent may change with time. Thus, typically each polity will be defined by a set of multiple boundaries, each for a specified period of time.