The GeaCron database has a sequence of political entities georeferenced by vector polygons since 3000 BC. These polygons are formed by a series of points defined by longitude and latitude. In the example, a sequence of the political entity Portugal is represented as an independent polygon separated from its natural location. As the configuration of this political entity varies throughout history, it can also be seen that it affects the polygons of other adjacent political entities.

The GeaCron database contains more than 280 of the most significant routes since 3000 BC. These routes are delimited by dates and consist of multi-lines composed of lines (more than 1,400) formed by a sequence of points georeferenced by latitude and longitude. It facilitates studies on cultural distance, expeditions, invasions, migrations, trade or economy. It also allows, in addition to viewing a route on a specific date, functions such as progressively displaying the points that make up said lines. The example shows a sequence of points on the route followed by James Cook between 1772 and 1775 on his second voyage.

For a given date and country, the GeaCron database contains the following information: Perimeter of polygons belonging to the country, length of coastline, at a scale of 1:5000000, and approximate surface of ​​the selected political entity. It also contains the surface occupied by the selected country and the surface of ​​the selected country occupied by other countries. In the example, Germany was selected in 1945 and it shows the proportion of the surface area of ​​this country with respect to the rest, the proportion of the length of coastline and land border, the surface area of ​​the country and the largest one on the selected date. It also shows the surface area occupied by this country and the surface area of ​​Germany occupied by other countries.

The GeaCron database contains around 3,000 events that have led to border changes since 3000 BC affecting, in most cases, more than one political entity. It provides assurance of the design of maps, allows for their rational modification, and facilitates the work of all kinds of analysis for researchers. The example shows the reasons for border changes in the North American region in 1803 and in Persia in 331 BC.

The GeaCron database contains estimates of the average temperatures per month and year for the political entities in the database since 3000 BC. In this way, the evolution of the mentioned temperatures can be observed as the political entities expand or contract. The example shows a graph of the evolution of the average temperature in the month of January for the political entity Rome, while at the same time maps are displayed coinciding with clear increases or decreases in temperature.

Additionally, the monthly evolution of temperatures at a global level could be shown for each year together with the layout of the political entities in that same year. The example shows the monthly sequence of temperatures for the year 1000.

The GeaCron database contains estimates of the annual population for political entities since 1 AD. It allows new approaches or considerations to be brought to Universal History from many angles such as economic, social, cultural or military. We will soon incorporate this information from 3000 BC to 1 BC.

The example below shows the estimated population of the political entity of Venice in the year 1553.

This example shows graphs with political entities colored according to a range of population density. These data have been calculated using demographic information and surface area for each political entity in the years 1004 and 1435.

The example below shows the evolution of the world population from the year 1000 to the year 2000. The blue line represents the estimated population according to data obtained from external sources studies. The red line represents the estimated population of all political entities in the GeaCron database.

The GeaCron database contains around 500 of the most relevant timelines since 3000 BC consisting of countries, military conflicts, scientific advances, artistic, philosophical, literary and religious movements, subdivided into more than 13,200 periods consisting of rulers, wars, inventions, artistic, philosophical, literary authors and religious evolutions. In addition, these periods have associated facts such as deaths, battles or artistic or literary works. It is a structured information and is one of the concepts that facilitates the study of Comparative History. The example shows the correlation between several countries and the artistic movement of Renaissance Painting.

The GeaCron database contains the names of more than 1,300 countries and civilizations since 3000 BC. georeferenced by latitude and longitude and delimited by the dates. Allows functions such as displaying a certain name in a specific location and in a specific date on the map or knowing which countries or civilizations existed on a certain date, according to the mentioned Geacron database. The example shows a sequence of a subset of a table with different georeferenced country names for the year 1940 and their subsequent location on the map.

The GeaCron database contains the names of more than 850 localities since 3000 BC. georeferenced by latitude and longitude and delimited by the dates on which they become relevant. Allows functions such as displaying a certain locality in a specific location and in a specific date on the map or knowing which localities existed on a certain date, according to the mentioned Geacron database. The example shows a sequence of georeferenced localities for the years 1410 BC, 210 BC and 2000. For the latter year, the georeferenced information in an external file has been used.

The GeaCron database contains more than 2,800 of the most significant events since 3000 BC. georeferenced by latitude and longitude and delimited by the dates on which these events take place. These events are represented by specific icons and by their names. Allows functions such as showing a specific event in a specific place and in a specific date on the map. The example shows a sequence of georeferenced events for the year 1781.

What is GeaCron?

GeaCron provides the world's most powerful geo-temporal database for historical research and education.

GeaCron’s mission is to make historic information universally accessible for everyone through intuitive and attractive geo-temporal maps as well as configurable timelines.

We have created a system to represent the historical events and the geo-political, climatic and demographic maps of the world's political entities, for any given historical period.

GeaCron is based on a vector structured database. We developed a real temporal GIS system.

The following chapter presents the primary sources used to prepare this information as well as the detailed exposition of the methodology utilized. We have collected information from maps encompassing 5000 years and the whole world, using many different sources such as libraries, historical atlases, university sources or Internet.

Each border change, after examining the information contained in the mentioned sources, is supported, at least, by one historical fact that explains said border change. This information facilitates a possible rational and consistent modification of the maps.

This design allows the GeaCron database to be accurate, configurable, flexible, scalable and it facilitates increasing historical information, almost unlimited.

By clicking on the following link you will obtain the list of the main sources consulted for the preparation of the assets described above, as well as the methodology used.

Additionally, for historical temperatures we have consulted the following sources:

Global temperatures 1880 - Present Day. GISS Surface Temperature Analysis

Global temperatures 20,000 years ago - 2,000 years ago. From Clark et al., 2016, Nature Climate Change

Datasets can be obtained by accessing here

Gridded Climate Data. Link

Temperature 1951-1980. Link

Additionally, for historical demographics we have consulted the following sources:

Maddison Historical Statistics. Maddison Database 2010. Link

Josiah C. Russell (1972). "Population in Europe". The Fontana Economic History of Europe: The Middle Ages. Tomo I Edición de Carlo M. Cipolla. Glasgow: Collins/Fontana, pp. 25-71

The Black Death 1346-1353: The Complete History, Ole J Benedictow.