Canonical? A canonical district referred to buildings where canons lived. They had to live next to the bishop, because the cathedral was the church where the bishop had his seat (cathedra). In the 9th century, the district was built in order to house the canons on the outskirts of the cathedral. This district was surrounded by a big wall from the Middle Ages: the cathedral and its buildings became a true city in the city!
During the French Revolution, the district lost its religious function. In the 19th century, all the buildings were destroyed. Nowadays, the area houses public and administrative buildings (for instance the prefecture, at the bottom of rue Pothier).