Zen, traced to the ancient teachings of the Buddha Shakyamuni, took root in China via India around 1,500 years ago through the first Zen patriarch, Bodhidharma. Spread there by the priest Linji Yixuan (Rinzai Gigen, died 867), it was transmitted to Japan in the Kamakura Period (1185-1333) and patronized by the elites — imperial family, nobility and warrior class.
In the Edo Period (1603-1868), it spread to the wider populace, most prominently by Hakuin Ekaku (1685-1768), a figure who since the late 19th century known is mostly as a painter and calligrapher, though was foremost an extraordinary religious teacher. "The Art of Zen: From Mind to Form" at the Kyoto National Museum commemorates Linji Yixuan's 1,150th and Hakuin's 250th memorials of their deaths.
Zen places emphasis on enlightenment through meditation and mind-to-mind transmission of Buddhist knowledge. True understanding is not conveyable in words. But Zen is a many varied thing and revels in paradox. Without doubt it is the most widely recognizable form of Buddhism worldwide, particularly since its boom in the 1950s and '60s that resulted in everything from California communes to Robert Pirsig's"Zen and the Art of Motorcycle Maintenance" and Bart Simpson solving the riddle of "the sound of one hand clapping."