There is a Greek goddess called Iris. Daughter of Thaumus - a god of the sea and Electra - a cloud nymph. Iris was the personification of the rainbow. Her job was to bring messages from the gods to mankind. Kind of an apt deity for this flower to be named after. Blue Flag bloom in the spring close to water. While I've only seen this wild variety in blue, hybrid iris come in a myriad of "rainbow" colors. As for being a link between the gods and humanity, when I find this flower in bloom I think it's pretty divine. I make one more connection between the flower and the goddess. The goddess Iris's sisters were the Harpies - evil female monsters that circled mortals tormenting them w/ noise and trying to snatch food. Something I'm reminded of when I'm standing in the swamp attempting to bring the camera into focus on the flower while mosquitoes swarm around.