In ancient times, purple garments were worn only by royal and imperial families because of the rarity and costliness of the dye. Born in the purple (rather than to ) may have specific reference to the fact that Byzantine empresses gave birth in a room in the palace at Constantinople whose walls were lined with the purple stone porphyry. The title ‘the Porphyrogenitos’ or ‘Porphyrogenita’ was used for a prince or princess born in this room.