Spain officially became the 16th member of NATO.
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Andrew Jackson killed Charles Dickinson in a duel.
The First Balkan War came to an end with the signing of the Treaty of London.
SpaceX's Crew Dragon Demo-2 launched from the Kennedy Space Center in Florida.
Seth MacFarlane's 'A Million Ways to Die in the West' was released to theaters.
Finding Nemo, directed by Andrew Stanton, was released in the US & Canada.