This interactive treemap visualizes mortality data from the 20th century, sourced from David McCandless’s public data collection. Built with D3.js and rendered as an SVG with animations, the visualization encodes death tolls through rectangular area, allowing viewers to compare the scale of deaths across causes such as famines, natural disasters, and extreme weather events. The data is hierarchically organized by cause and subcause, and hovering or interacting with the rectangles reveals specific events and estimated casualties. The treemap provides a stark, at-a-glance perspective on the century’s human cost, highlighting the enormous impact of famine—particularly in China, the Soviet Union, and India—while contextualizing these figures against deaths from earthquakes and extreme weather. The animation helps guide the viewer through the hierarchy, making the comparative scale of each disaster immediately visible.