On this day in 999 AD, the greatest sea battle of the Viking age was fought.
After his fleet was ambushed, King Olaf of Norway fought on the deck of his flagship, The Long Serpent, until it was overrun.
When all was lost, he jumped into the Baltic Sea and was never seen again.
Born today 214AD Aurelian. His military successes were instrumental in ending the Roman Empire's Crisis of the Third Century, earning him the title Restitutor Orbis or 'Restorer of the World'.
Today in 1756, Prussia's Frederick the Great attacks Saxony setting off the Seven Years War in Europe. The conflict, which is already being fought by France and Britain in North America, sees fighting spread to European colonies in Africa, India and the Far East — a world war.
On this day in 1813, a French army blunders into a column of Prussian and Russian troops during a thunderstorm near Liegnitz (in present-day Poland). The skirmish quickly escalates into the Battle of the Katzbach, one of the largest clashes of the Napoleonic Wars.
On this day in 1870, German forces win a pair of victories in the two-week-old Franco-Prussian War. The battles of Spicheren and Wörth pave the way for the conflict's decisive showdown at Sedan in September.