Short answers, pulled from the story.
The oldest evidence of a large-scale battle in Europe dates to the 13th century BC, where more than 4,000 warriors fought in the Tollense valley. This discovery challenges the assumption that recorded history begins with the first written accounts, revealing that organized warfare was already a massive, complex enterprise thousands of years before the invention of the alphabet.
The first battle in relatively reliable detail in India was the Battle of Megiddo, recorded by the Egyptian military scribe Tjaneni in the 15th century BC. The earliest recorded battle in India was the Battle of the Ten Kings, but the Battle of Megiddo provides the first reliable account.
In 1575, the Japanese general Oda Nobunaga successfully implemented a volley fire technique twenty years before evidence of such a technique appeared in Europe. This tactical innovation allowed infantry to replace cavalry as the primary force, changing the rhythm of battle.
The nuclear submarine was invented in 1955, meaning submarines no longer needed to surface as often and could run more quietly, evolving into underwater missile platforms. This development marked a new era in naval warfare following the introduction of the self-propelled torpedo and the first navigable submarine by Cornelius Drebbel in 1624.
The Society for Military History has published The Journal of Military History since 1937. Academic historians concerned with military topics have their own scholarly organization, which continues to publish this journal today.
The actual bomber that dropped the atomic bomb on Japan became the focus of an angry national controversy with veterans attacking curators and historians when the Smithsonian Institution planned to put its fuselage on public display in 1995. The uproar led to the cancellation of the exhibit.