Samhain, a Celtic festival meaning "summer's end", has evolved into which holiday?

Begun in 1967, which became the USSR's third crewed space program? Beginning in September 1940, the German bombing of which capital became known as the Blitz? Begun in the 2nd century BC, which trade route stretched thousands of miles from China to the Mediterranean? Begun on January 21, 1968, the battle for which U.S. Marine outpost may have been a North Vietnamese diversion before t… Begun on January 1, 1660, whose diary includes vivid accounts of the Great Plague and the Great Fire of London? Begun under Napoleon, which roughly 160-foot-tall Paris landmark was completed in 1836? Executed on October 29, 1618, which English adventurer is said to have declared, "So the heart be right, it is no matte… "Behind These Hazel Eyes" was a hit for which "American Idol" winner?