Portrayals of the crucifixion of Christ derive their visual details mainly from the four Gospels. Other details usually point to the theology of the Crucifixion, especially the doctrine of Christ's sacrificial atonement for the sins of men and women.
In the first four centuries the Crucifixion was rarely represented in Christian art; indeed, the earliest known image is an anti-Christian graffito. Such images as we do see in this period tend to be symbolic rather than representational, as in the case of the Sarcophagus of Domatilla, which brings together symbols of the Crucifixion with symbols of the Resurrection. This juxtaposition of the pathos of Christ's death with more positive Christian themes will be a feature of Crucifixions down through the centuries, for example in the Edenic imagery of the apse mosaic at St. John Lateran.
The fifth century provides a few examples of Crucifixions in which the event is presented with simple literalism (a door panel, an ivory box), but even these maintain a stately dignity in the figures of Christ and even of the thieves.
In the sixth century we start to see the familiar compositional choices that will characterize most Crucifixions in ensuing years. In a Syriac illumination of the time we see Christ between the two thieves named Dismas and Gestas, Mary and John standing together to the left of the cross, Longinus with the spear and Stephaton with the sponge closest to the cross and on either side of it, the crowd, the sun and moon to represent the darkness that came over the earth, the soldiers throwing dice for Christ's cloak, a background representing Jerusalem, and most importantly a companion image of the Resurrection.
Longinus and Stephaton are also closest to the cross, and on either side of it, in another sixth century piece, a Palestinian icon. Mary and John stand off a little distant, each on one side of the cross. Eventually Mary and John will supplant these two minor characters from their position closest to the cross, though one eighth century plaque in France has only the two men at the foot of the cross.
Pathos is not the goal in these early images. Rather, one is led to consider the Crucifixion's relation to Christian truth and Christian liturgy. Christ is depicted in a colobium, either out of reverence or quite possibly to suggest his simultaneous role as priest and victim in the sacrifice of the Cross. (The thieves always wear the simple perizoma or loincloth.) His arms are almost always at right angles to his trunk, as if in a liturgical gesture. In one example from the eighth century, blood flows from his side but without any indication that this is painful or other than appropriate.
The colobium continues to be seen in some western Crucifixions through the twelfth century, but eventually it is entirely supplanted by the perizoma as medieval images become at the same time more emotional and more literal. We now find a highly emotional Mary Magdalene embracing the foot of the cross and angels lamenting the death of their Lord (example). The latter are sometimes portrayed catching Christ's blood in chalices, a reference to the Eucharist that raises the image above the merely maudlin (example). One unusual Crucifixion painting by Jacopino da Reggio has St. Francis hugging the base of the cross in a Magdalene-like attitude. (Not represented here, the painting may be seen in the Metropolitan Museum of Art in New York City.)
Literal touches include skulls to refer to Matthew 27:33 and a figure in the crowd pointing to Christ as if saying the words of Mark 15:39, "Surely this was the Son of God." (example)
At and after the end of the middle ages many Crucifixions become very literal about the violence suffered by Christ's body (example).
Starting with the 16th century artists sought other ways to be dramatic (examples: Joos van Cleve, Rubens, Breughel, Rembrandt). In our own age, with the notable exception of Mel Gibson's Passion of the Christ, violence is eschewed and many artists have returned to stylized and/or symbolic portrayals of the crucifixion, though sometimes with quite different meanings (examples: Subirachs, Picasso, Chagall).
Feast day: The anniversary of the Crucifixion is observed on the Friday before Easter.
At left, a Venetian ivory binding plaque
Group of Crucifixion sculptures, Spain
Ex-voto from Spanish America
Gospel accounts of the Crucifixion:
Golden Legend #53: html or pdf
Also see Crosses and Crucifixes, Adam and Eve