Artists Paul Gauguin and Vincent van Gogh had a volatile and somewhat lopsided friendship. Van Gogh was living in Arles in 1888, and wanted Gauguin to come live with him there, where he imagined they would paint together and found an artist's colony. Gauguin had a sense of foreboding about that plan, but finally relented and said he would go to Arles for a temporary stay.
Despite his destitution, Van Gogh spent whatever money he had on two beds, which he set up in the same small bedroom. Seeking to make his modest sleeping quarters “as nice as possible, like a woman’s boudoir, really artistic,” he resolved to paint a set of giant yellow sunflowers onto its white walls. He wrote beseeching letters to Gauguin, and when the French artist sent him a self-portrait as part of their exchange of canvases, Van Gogh excitedly showed it around town as the likeness of a beloved friend who was about to come visit.
Gauguin finally agreed and arrived in Arles in mid-October, where he was to spend about two months, culminating with the dramatic ear incident.
During that time, Gauguin saw Van Gogh descend into his mental illness. Things came to a head two days before Christmas, when Gauguin went to a hotel for the night. Gauguin had escaped being cut by a razor by Van Gogh, who instead went home and cut off his own ear. Read Gauguin's account of that night and the aftermath, from the book Paul Gauguin’s Intimate Journals, at Brain Pickings. -Thanks, Tim!