In a Newark jazz club last month, Lorenzo Morrast proudly watched as his 16-year-old daughter Alexis delivered a soulful, throaty rendition of an old tune that laments of the tribulations of African-American folk hero John Henry.

“Early ‘70s was a tough time for the city,” the Newark native said, referring to the period after the summer of 1967, when violence erupted there and in more than 100 other U.S. cities, fueled by long-simmering economic and racial tensions.

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