The front lines are simplified reconstructions based on standard accounts of the campaigns; their position is accurate to within a few tens of kilometres. The hatched areas show territory that one side held beyond the 1914 borders at the end of the chapter. Front lengths and areas are measured on the map and count only active fronts.
Casualty figures include killed, wounded, missing and captured on both sides. They vary widely by source; the ranges given come from the infoboxes of the English Wikipedia (as of 2026). The number of dead per country follows the table “World War I casualties” there.
Soldiers in the Prologue: strength after mobilisation in August 1914, from the table “Kräfteverhältnis” (balance of forces) in the German Wikipedia article “Erster Weltkrieg” (as of 2026, based on G. Hirschfeld et al., Enzyklopädie Erster Weltkrieg). All mobilised men are counted, including reserve troops and garrisons, not just the troops at the front. Other sources sometimes give considerably different figures, for Russia about 4.5 to 6 million.
Home Front and Diplomacy: the map shows the places where decisions were made and the routes of notes, treaties and declarations of war between the capitals. Fronts and occupied territories appear faded, as they stood on the chapter's date in the military timeline. Places off the map, such as Washington or Mexico City, are labelled at the edge of the view; arrows to them end at the map edge. When you switch timelines, the map jumps to the chronologically nearest chapter, unless a chapter was already selected there.
Relief: ETOPO grid (20 arc-minutes) with generated detail, exaggerated about 28 times. Coasts, lakes and rivers: Natural Earth. 1914 and 1920 borders: historical-basemaps (A. Ourednik, GPL-3.0) and Natural Earth provinces. In the Epilogue, ceded territory is the difference between the 1914 and 1920 borders; the split between Saint-Germain and Trianon follows present-day provinces, and the plebiscites of 1920/21 are only marked.
A portrait of Richard Müller is still missing; he appears with his initials.
Controls: drag to rotate, scroll or pinch to zoom, arrow keys for chapters, tabs below the title for the timelines.