William Playfair (1759–1823)
William Playfair is considered the father of statistical graphics, having invented the line and bar chart we use so often today. He is also credited with having created the area and pie chart. Playfair was a Scottish engineer and political economist who published The Commercial and Political Atlas in 1786.
This book featured a variety of graphs including the image below. In this famous example, he compares exports from England with imports into England from Denmark and Norway from 1700 to 1780.
John Snow (1813–1858)
In 1854, a cholera epidemic spread quickly through Soho in London. The Broad Street area had seen over 600 dead, and the remaining residents and business owners had largely fled the terrible disease.
Physician John Snow plotted the locations of cholera deaths on a map. The surviving maps of his work show a method of tallying the death counts, drawn as lines parallel to the street, at the appropriate addresses. Snow’s research revealed a pattern. He saw a clear concentration around the water pump on Broad Street, helping to find the cause of the infection.
Charles Joseph Minard (1781–1870)
Charles Joseph Minard was a French civil engineer famous for his representation of numerical data on maps. His most famous work is the map of Napoleon’s Russian campaign of 1812 displaying the dramatic loss of his army over the advance on Moscow and the following retreat.
You can see how many soldiers are still marching and how many died. Drawn in 1869, it is described by many as the best statistical graphic ever drawn. It represents the earliest beginnings of data journalism.