Data Trails No. 9 – Snapshots from the history of data visualisation
Picture this: you need to plot data describing two large geographic entities, spanning the enormous period of 1,700 years, and you have no interactive tools at hand. No software, no templates, no filter, no button, no zoom, no switch. How in the world are you going to create a compelling visualisation for this data set, one that enables both overview and insight into the details?
Girolamo Andrea Martignoni is a bit of a mystery. He lived during the first half of the 18th century (probably in Rome) and seems to have been a catholic scholar. But that’s pretty much all we know about him – except that he released a set of mind-blowing history maps in 1721. Look at this strange beauty here:
Girolamo Andrea Martignoni, “Carte Historique De La France Et De L’Angleterre Depuis La Naissance De Jesus-Christ Jusqu’a L’An 1700”, published in Rome in 1721.
Its ambitious title (intricate and ornate as all 18th century titles) hints at what Martignoni has tried to achieve: a chart showing the history of France and England from the nativity of Jesus. Quite a task you would think, given the sheer endless series of kings and queens, territory acquisitions and losses which have shaped the history of both countries. Martignoni plots this data in an interesting combination of classic maps (showing the two territories in question) and – set into the center of the piece – a chronographic tableau depicting the history of both countries.
Now while the maps of France and England in the upper left and right corners are pretty straightforward, the centre piece does well deserve a closer look. What is this strange territory projected into the middle of this graphic, with a nondescript sea labelled “Roman Empire” at the top, and crossed by countless oblong rivers in its lower part? The labels along the sides provide orientation: the “latitudes” in this central part of the graphic refer to the centuries, running from the year zero AD on top down to the year 1700, thus constructing a fictitious land of European history.
Girolamo Andrea Martignoni, “Carte Historique De La France Et De L’Angleterre…”, detail of the upper part of the chronographic tableau.
See how the Roman empire forms an endless sea, structured only by several obscure islands adorned with coins accounting for historical events. This is the beginning of our story here. Around the year 400 AD, this non-descript “Roman Empire” splits into two major rivers labelled the “Kingdom of England” and the “Kingdom of France”, and this is where things start to go wild. Countless arms and creeks reach out and divert rectangularly to signify the countless little fiefdoms which covered most of France and England throughout the middle ages.
It is glorious to see how Martignoni has used all available “map space” in this central tableau and filled it with details and hints to historical and topographic data. It is also mindbending because the look of this central chronographic tableau makes us think it is a map – where the space is clearly defined by a grid of coordinates. This is all but true. While the latitudes are indeed clearly defined by the time running downwards, Martignoni divides the space in between at his convenience, allocating elements at will and making sure everything fits in neatly, including labels, pictograms, labels and explanations where they fit best.
Girolamo Andrea Martignoni, “Carte Historique De La France Et De L’Angleterre…”, detail of central part of the chronographic tableau.
For instance, this central part includes a legend which explains the system of the rivers: how they come into being, evolve, grow, divide or unite, or end in no-mans-land. This is set into a wild “landscape” crossed by myriad French and English rivers. Above the label, one river ends in a curious inset picture of the Pyrenees mountains, depicted here for no obvious reason.
Now while this wild plot of historical data may leave us puzzled today, wondering how in hell this map may ever have helped anyone get a clear grasp on the data displayed here, this piece, along with its siblings, is acknowledged today by historians of cartography and chronography as a bold and early attempt at creating a visual timeline. We do know some designs by contemporaries of Martignoni (such as the “Chronography” by Jacques Barbeu Du Bourg or the “New Chart of History” by Joseph Priestly) which are more in line with our modern idea of a timeline – featuring regular and ordered intervals of time and allocating events accordingly. Martignoni’s design, on the other hand, is particularly fascinating in how it conceives of time as a territory and sets out to plot this idea in an ornate map, merging data and imagination boldly into one intricate visual.
Images are from taken from the David Rumsey Historical Map Collection. For everyone interested in how the idea of the timeline has developed I recommend the excellent book “Cartographies of Time”, published in 2012 by Princeton Architectural Press.
Sandra Rendgen is the author of two bestselling books on data visualisation and infographics, both published by Taschen. Currently she is getting lost in the history of data visualisation.