Irian, the Eternal Dawn

Irian is the plane of light and hope, the wellspring of positive energy which is the foundation of light, life, and love. The regions of Irian reflect the idea of beginnings and of resurgent life: fertile lands untouched by any tool, glittering crystal forests, and thriving homesteads and communities. Angels dwell in a grand city reflecting the first days of a glorious empire. The sun never sets here.
Positive energy flows into the material plane from Irian, and the denizens of Irian believe that the simple fact of their existence helps the mortals of the Material Plane. The celestials of Irian are also those most likely to respond to planar ally and similar spells.