This is going to be a TL that I will work hard on, because WWI is my favorite history topic, and I wanted to create the true WTEAWs, because back then, Europeans believed it was the WTEAWs, and thought it would last only six weeks.
***
1903
Serbian nationalism becomes a prominent force in Serbian politics with the advent of the terrorist group, Crna Ruka (Black Hand).
1905 - 1911
Revolutions break out in various countries: Russia, the Ottoman Empire, Mexico, and China.
1908 - 1909
The Dual Monarchy of Austria-Hungary annexes the Ottoman province of Bosnia-Herzegovina. This greatly angers the Ottomans. Sultan Mehmed V and the Committee of Union and Progress declare war on the Austrians; the Austrians declare war on the Ottomans; the Russians, seeing the Austrians as a threat, as it was pro-Serbian, declares war on the Austrians. Although inherent enemies since 1299, the Ottomans and Russians work out an "agreement of alliance" to temporarily to hold off the Austrians.
1910 - 1912
Britain, France, and Germany participate in an arms race and the Railway Wars, trying to gain as much territory, speed, and time as possible. Russia, although in a war with the Austrians, also participates. Germany "wins" the Railway Wars, and overpowers Britain, France, and Russia as the dominant European power.
1912 - 1914
Austria wins the "Four Years' War." The Ottoman Empire retreats and suffers massive casualties; the Russians are also weakened. Unrest erupts in the Balkans. To further dismantle the Ottomans, the Balkan states declare war on the Empire, and immediately dismantle it. The Ottoman State is on the verge of collapse.
Serbian nationalists assassinate Archduke Franz Ferdinand, heir to the Austro-Hungarian throne. War breaks out between both empires.
Germany forms an alliance with Italy and Austria-Hungary. The UK forms an alliance with France, Belgium, and Portugal. Germany tries to goad the fractured Ottomans to join them, but fail. Bulgaria and various other Balkan states join Austria in the Central Powers. Serbia joins the Allies. Russia, having economic ties to Serbia, joins the Allies. The Ottomans, realizing that the Allied system of alliances was fulfilled, reluctantly join the Central Powers after a promise of the return of Bosnia and other lost territories. To counter an Italian offensive, the Allies get a successful alliance out of Spain.
Alliances as of 1915:
Allies: UK, France, Belgium, Spain, Portugal, Russia, Serbia
Central Powers: Germany, Austria, Italy, Bulgaria, Romania, Ottomans
TO BE CONTINUED...