"Or Didn't They?"

"It all starts in 1612, when an educated, bilingual, actual Irish spy named Thomas Shelton translates part one of the 'Quixote'—to rapturous acclaim and sensational sales —as 'The History of the Valorous and Wittie Knight-Errant Don-Quixote of the Mancha.' About a year later, an aging William Shakespeare and his anointed protege, John Fletcher, co-write their third play together, 'The History of Cardenio.' That would be the same crazed, cuckolded Cardenio whom Don Quixote met in Chapter 23 of the novel, then helped reunite with his inamorata a hundred pages later.
"Yes, as the wittie Ring Lardner might have said, you could look it up. In 1613, almost surely without ever meeting in person, it was Shakespeare who helped usher Cervantes onto the British stage for the first time.
"Or so we think."

David Kipen in the Los Angeles Times wonders about connections between Miguel de Cervantes and William Shakespeare, who both died four hundred years ago this month.