Marcel Bouvier (January 1, 1827 - November 2, 1906) is Marge's great-great-grandfather. He had 9 children with Angelique Marceau. He looks like a mime. He is the great-great-grandfather in law to Homer Simpson and the great -great-great-grandfather of Bart, Lisa and Maggie Simpson.
His wife's maiden name and his first name (and his mime-like appearance) are based off the famous late French mime Marcel Marceau.
Before Marcel, the Bouviers appeared to be rich. It is unknown why Marcel became a mime and the Bouvier family became commoners.