Triple Entente / Allies
France, Russia, Britain, later Italy, the US and others -- a coalition that grew as the Central Powers shrank.
Peacetime armies of hundreds of thousands became millions. Rail timetables were mobilisation plans.
Navies enforced blockade and convoy; they did not refight Trafalgar, except in the inconclusive clash at Jutland (1916).
Systems
Central Powers
Germany, Austria-Hungary, the Ottoman Empire and Bulgaria -- never as integrated as Allied shipping and finance became.
Mass artillery
The dominant casualty-maker; shells per yard of front became a planning unit.
Blockade and U-boats
Economic war at sea, including the Lusitania sinking (1915) as a propaganda hinge.
Staff and rail
Mobilisation was a railway problem before it was a battlefield problem.
Medicine and psychiatry
Casualty clearing stations, facial reconstruction, and the contested category of shell shock.
Meters
Geographic reach
86
Industrial attrition
92
Memorial density
95
Naval blockade weight
80
Political shatter
90
Tech leap (relative)
78
Hotspots
Western Front
Flanders and northern France: Ypres, Somme, Verdun, Hindenburg Line.
Eastern Front
Tannenberg to Brest-Litovsk -- movement, then Russian collapse.
Gallipoli
April 1915-January 1916; ANZAC legend and Ottoman defensive success.
Mesopotamia/Palestine
Kut, Baghdad, Jerusalem, Damascus -- empire war with a long afterlife.
North Sea
Grand Fleet vs High Seas Fleet; Jutland 1916; blockade as daily strategy.
Materials
Shells and steel
The 1915 "shell scandal" in Britain showed industry as politics.
Nitrates and explosives
Haber-Bosch and Chilean nitrates -- chemistry as a strategic commodity.
Horses and fodder
Still a horse-powered war in logistics, even as tanks appeared.
Food and blockade
German turnip winter (1916-17) and Allied rationing as weapons systems.
Colonial and dominion formations -- Indian Army, ANZAC, Canadian Corps -- were not extras. They were part of the force.
This is a historical force picture, not a modern ORBAT or a training syllabus.