The German artist died in London almost 500 years ago. To this day, no one knows where in the city he was buried. He was a star of the Renaissance, an unflinching painter of death and horror in a time of rampant plague. Yet he ended up in an unmarked grave in London. Or so it has always been believed. While on lockdown, Jonathan Jones went on a mission to find the artist's bones. In this fascinating piece, he shares the results of his efforts for the Guardian.