Ensor's parade may well reflect the tradition of religious processionals, including the bawdy rites of Mardi Gras, and the more secular, nationalist pageantry of "Joyous Entry" paintings that for centuries had commemorated the triumphant return of militia or monarchs to their capital cities.
WSJ: A Macabre Kingdom of Masks | James Ensor | Christ's Entry Into Brussels in 1889 | By Mary Tompkins Lewis