Why Paint a Picture in a Circle? A Shape With No Corners to Hide In

A rectangle supplies horizontal and vertical edges that the composition can align with, and corners where secondary material can be placed without disturbing anything. A circle supplies neither. Every edge curves, so a figure standing upright sits against a boundary that departs from it in both directions, and there is nowhere to place a subordinate detail out of the way. The eye also moves differently, since a circular frame has no starting corner and encourages a rotating reading rather than a left to right one. Artists therefore arrange these compositions around the centre, use curved and diagonal elements to echo the boundary, and fill the narrowing upper and lower areas with landscape, drapery or architecture.

A set of solutions recurs across surviving examples:

• •Figures arranged in a curve or a circle within the frame
• •A seated or kneeling central figure, which fits the shape better than a standing one
• •Landscape filling the upper corners where a rectangle would have sky
• •Foreshortened figures leaning inwards to follow the curve
• •Architectural arches echoing the frame
• •Elaborate carved and gilded frames that emphasise the circle deliberately

The fashion is concentrated in fifteenth century Florence and the reason is a domestic object. A circular painted or carved tray was traditionally given to a woman on the birth of a child, used to carry food to her during confinement and kept afterwards as a family possession, and those trays were decorated on both sides with scenes appropriate to childbirth and family. The format migrated from that functional object into independent paintings for domestic display, retaining the association with the household and with the family, which is why so many surviving examples show the Virgin and Child or the Holy Family rather than the public subjects that altarpieces carried.

The circle is one of several departures from the rectangle and each imposes its own problems. A lunette is a semicircle, used above doors and altarpieces, and it forces the composition into a shape that is wide at the bottom and closes overhead, which suits a reclining or a rising figure. A vertical oval was fashionable for portraits, flattering the head and shoulders while cropping everything else. A triptych divides a composition across three panels with hinges, so the artist must make each part work alone and together. Ceiling paintings are seen from below at an angle that changes as the viewer moves, which requires distortion calculated for one viewing point. Each format is a constraint the artist accepts and then exploits.

A small number of works define the format. Botticelli produced several, including two large and celebrated ones in which the circular arrangement of figures echoes the frame directly. Michelangelo painted one of the Holy Family for a Florentine family around 1506, which is among his very few surviving panel paintings and which twists the figures into a spiral that has been argued over ever since. Raphael, Filippo Lippi and Domenico Ghirlandaio all worked in the format. Carved marble versions in relief were produced by Donatello and others, and Luca della Robbia's glazed terracotta roundels applied it to architectural decoration. The fashion faded in the sixteenth century and the shape has recurred periodically since.

A circle supplies no straight edges to align with and no corners to put anything in, so compositions are arranged around the centre with curves and diagonals echoing the boundary. The format descends from circular trays given to women at childbirth, which is why it concentrates in fifteenth century Florence and why so many examples show domestic religious subjects. Botticelli, Michelangelo and Raphael all produced notable examples.