Chronas History Application: Let’s travel in time together

In 2014, Dietmar Aumann had a simple but innovative idea: what if Google Maps could be used to travel back in time? Since then, the development of was a matter of time and collaboration. Come and read the story of this virtual map, which just like Wikipedia, is based on the collective knowledge of people around the world.

In January 2001, the 21st century was just beginning. Several events would give shape to a turbulent year, many of which reshaped the concept of globalization for good. Besides relevant political and economic developments, the field of technology in the internet age brought remarkable news this year, particularly with the official launch of Wikipedia, a free online -openly editable- encyclopedia. What started in 2000 as a regular encyclopedia, controlled by a small group of experts, turned into the world of wiki (Hawaiian word meaning “quick”), which is a website based on collaborative user-generated content in user-editable pages.

In spite of criticism and potential problems, which are pointing towards the lack of accuracy and biased information, Wikipedia grew rapidly. Up to 2019, English Wikipedia has almost 6 million articles, while more than 40 million articles are available in 301 different languages. According to a research published in Nature in 2005, which compared entries from Wikipedia and the Encyclopedia Britannica, the issue of inaccurate content is actually less of a problem, since no major differences in terms of errors were found among the two web sources.

Considering how Wikipedia articles are written, that result might seem surprising. A solar physicist could, for example, work on the entry on the Sun, but would have the same status as a contributor without an academic background. Disputes about content are usually resolved by discussion among users“.

Jim Giles, writing for Nature.

This set-up, launched in 2001 and expanded throughout internet until present times, inspired Dietmar Aumann, a software developer born in Germany with experience in Finland, Sweden, Belgium and the US. With a collaborative mindset, Dietmar launched in 2015, which is a map application that combines Google Street View, Wikipedia and Google Earth, but adding the components of time and history. The basic idea for Chronas, Dietmar says, came from Google Maps. “I thought, wouldn’t be cool if you would have the ability to jump back a hundred years, or even a thousand or two thousand years, and see how the borders of the country looked back then?”.

Such original curiosity fueled the idea of having multiple types of data in the same site, embedding a chronological and a cartographic approach to the accumulated knowledge of the internet. By this way, an specific point in the map can be linked to a particular era, while describing the multiple social, economic, and political developments of the time. This description, Dietmar says, is also diverse, as it can be nurtured by Wikipedia pages, images, videos and audio clips, as well as primary sources. “So for example, you could have the siege of Constantinople linked to the city of Constantinople, linked to the Byzantine empire, which is as well then linked to a video of the Byzantine empire, which is then linked to one of the emperors, and so on. So basically you can jump from one article to the next and the next, kind of like how Wikipedia works on its own”, Dietmar says. With Chronas, “people can get lost and spend a lot a time in history, and by doing so, learning about it”.

Besides, the concept of mapping allows the user to see the historical development of the world in an interconnected way, as the map is showing the state of affairs in different zones at the same time. What happened in Asia when Rome dominated Europe? What happened in Arabia when Kublai Khan proclaimed himself the emperor of China? These are questions that can be answered through Chronas.

Collaboration: accurate information is a collective endeavor

After three years of operation, Chronas is a history map application with over 50 million data points. How is it possible for a single person, or a single team, to curate and edit that immense amount of information? “So, in my view, the only way to do that is to have a community of history enthusiasts and professionals who spend time and curate the data”, Dietmar replies.

That is how Chronas was born as a wiki, this is, a website that can be created and edited by the users themselves. “Everyone who is registered at Chronas can do that. They can re assign data to specific countries and specific years, they can delete specific markers and link them to other entities, so everything Chronas is based on is editable by the users and the community as a whole”, Dietmar says. Improvements have been introduced in the later years, in order to facilitate the user-generated edition and revision of the user-generated content. Thus, as the wiki systems works, inaccurate information in Chronas will be corrected by the community, which up to 2017, was composed by more than 6.000 people, including historians, researchers, and experts.

Yet as the famous quote goes, with great power comes great responsibility. Wiki are often criticized for being an easy subject of malicious individuals, who driven by whichever agenda can vandalize the system by providing wrong information. In order to tackle this unwanted development, Chronas is also based on a revision system. “If a user edits something, that is tracked and can be reverted by other users”, Dietmar says. Besides, users can report bugs in the Forums provided by the system, which are also often used to solve historical disagreements.

Therefore,, just as any wiki system, can only be sustained by a solid base of contributors, who can share their time and passion for history with the a broader community and the general public. By this way, the development of innovative learning tools is in hands of the educators themselves, putting technology at the service of history.

Would you like to collaborate? Go to and share it within your own network!

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