The Idirans are a fictional race in the Culture universe created by Iain Banks.

Physique

Full-grown Idirans stand about three meters tall on a tripod of legs and have two arms. A third, vestigial, arm has evolved into a chest-flap which the Idirans use to create loud, booming warning signals. They have a saddle-shaped head with two eyes at each end of the saddle. Idirans do not die of natural causes and are very resilient against physical damage, protected by a natural keratinous body-armour. They are dual hermaphrodites, each half of a couple impregnating the other. After one or two pregnancies Idirans lose their fertility and develop into the warrior stage, reaching full size and weight, the armour hardening fully. Idrians are capable of taking enormous amounts of damage and can survive massive trauma that would kill a human being instantly-for example, losing a large fraction of their head.

Religion and war

The Idirans are a deeply religious people and believe in a single, rational God who wants a better existence for his creation. Everything in life has its place and it is desirable to bring about order by putting things into their right places. This belief developed while they were struggling for survival in the harsh and chaotic conditions of their home world. Once they had tamed their environment they lived in peace and solitude for forty-five thousand years until they were almost made extinct by alien invaders. In response, (and in reflection of their physical change from breeder to warrior), they turned into a warrior race and attempted to conquer and convert all other races in the galaxy to bring about the order their God desires. This successful and brutal expansion eventually resulted in the Idiran-Culture War.