On this day in 1968, the U.S. Congress repealed the requirement for a gold reserve to back US currency.
On this day in 1969, the United States began secretly bombing the Sihanouk Trail in Cambodia, used by communist forces to infiltrate South Vietnam.
On this day in 1990, 12 paintings, collectively worth around $300 million US, were stolen from the Isabella Stewart Gardner Museum in Boston, making it the largest art theft in U.S. history.
On this day in 2014, the parliaments of Russia and Crimea signed an accession treaty.