July 15 in Military History — On This Day

⚔️📍 Grunwald, Poland1410

Battle of Grunwald — Poland-Lithuania Crushes the Teutonic Knights

A Polish-Lithuanian army under King Władysław II decisively defeated the Teutonic Knights — then the most powerful military order in Europe — in the largest battle of medieval Europe. The Grand Master of the Order was killed along with much of the Order's leadership.

Grunwald broke the Teutonic Knights' power permanently and established Poland-Lithuania as the dominant power of Central Europe.

Outcome

Polish-Lithuanian victory; Teutonic Knights permanently weakened

Casualties

40,000

Second Battle of the Marne

Germany's last offensive of the war — Ludendorff's 'Peace Offensive.' French intelligence obtained the exact date and time of attack. General Gouraud deliberately thinned his front line, pulling his main force back — the German barrage and assault fell largely on empty trenches. When German forces crossed the Marne, a massive French-American counterattack, Operation Marneschutz-Reims, smashed the assault. Marshal Foch then launched a devastating counteroffensive that pushed Germany back 40 miles in three weeks.

The true turning point of WWI. Ludendorff called August 8 — the start of the Allied Hundred Days Offensive — 'the Black Day of the German Army.' After the Second Marne, Germany had no more reserves. The war was effectively decided, though three more months of fighting remained. Ludendorff told the Kaiser the war was lost.

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Battle of Damascus

Rebels launched 'Operation Damascus Volcano' on July 15, 2012, simultaneously attacking multiple districts of the capital in the most audacious offensive of the war's first year. A suicide bomb two days into the battle killed the Syrian defense minister, the deputy defense minister, and Assad's brother-in-law Assef Shawkat at a National Security headquarters meeting — the highest-level assassination of the conflict. Despite shocking the regime and briefly seizing several suburbs, rebel forces lacked the manpower to hold ground against armored counterattacks and were pushed back within days, demonstrating both the rebels' capability to threaten the capital and their inability to deliver a decisive blow.

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