Claude Monet, during a painting campaign at Varengeville on the Normandy coast in the summer of 1882, created three works that depict a medieval church in morning light. Could we combine astronomical analysis of the direction of sunlight and shadows, computer calculations of tide schedules in 1882, meteorological archives, and remarks in the artist’s letters to find the calendar dates of the scenes captured by Monet? Vincent van Gogh created Lane of Poplars at Sunset early in his artistic career at the town of Nuenen in his home country of the Netherlands. Can we employ visits to the site, observations in meteorological archives, clues in the artist’s letters, and astronomical calculations to determine the precise date and time when Vincent was inspired to paint this view? El Greco’s The Agony in the Garden portrayed Jesus in the Garden of Gethsemane on the night before the crucifixion. El Greco included a full Moon in the sky. Can we combine evidence from the narratives in the Gospels and from the calendars of that era to establish the lunar phase on the night in the Garden of Gethsemane? By depicting a full moon in the sky, did El Greco correctly follow Biblical traditions and chronology?