The planet Imsk first appeared in the pages of Superboy and the Legion of Super-Heroes #234, (December, 1977).
Imsk is a fictional planet in the 30th and 31st centuries DC Universe. It is the homeworld of the famous Legionnaire Shrinking Violet, as well as the villain Micro Lad who has been both a member of the Legion of Supervillains and a separatist faction of Imsk.
All Imskians have the ability to shrink, some as far as microscopic size. As such Imsk's factories are particularly successful in the construction of micro-circuitry.
Imsk has often been at odds with the United Planets, a fictional governing body depicted as active in the 30th and 31st centuries over its claimed territory in its sector of space. The government of Imsk has requested for a larger space zone around itself on several occasions however the U.P has bared this from occurring.
Universe: Pre-Zero Hour, Post-Zero Hour, Earth-Prime
Galaxy: Milky Way
Star System: Irulan
Province: United Planets
The planet of Imsk's humanoid inhabitants did not originate on Imsk, but were the descendants of a Krill Colony. They arrived on Imsk approximately a million years ago. After settling the planet began to shrink on the eleventh year, and for fifty days the planet continued to dwindle to a smaller and smaller state, but the residents of the world effectively remained in their natural heights. One of the colonists was able to discover a peculiar energy from radioactive boulders, and he turned that radiation on the other denizens of the planet. This altered their genetic structure and the people and they began to shrink. Now genetically altered the population would have the ability to shrink and it became a hereditary trait passed down from generation to generation.
The planet Imsk has a similar origin to the Pre-Zero Hour continuity. Although a member of the United Planets, there is a strong separatist movement that has at times controlled the government and withdrawn from U.P. membership. During the economic collapse of the United Planets, Imsk fought a war with the planet Braal, whose natives all possess magnetic abilities. The Imskians had feared an all out scaled war, and due to the economic collapse decided to develop a weapon that turned the Braalian magnetic fields against them, causing them to explode. Imsk and Braal eventually did go to war, with Imsk winning after the detonation of a magnetic bomb at Venado Bay that devastated the magnetism-controlling Braalians and cost Rokk Krinn, formerly Cosmic Boy, his powers. Shrinking Violet, who had fought in the war, was imprisoned after she protested the use of this weapon.
The Legionnaires have assisted the government of Imsk on several operations. Along with the Imskians the Legion coordinated on a mission outside of the planet Imsk. A flock of space dragons attempt to nest on the planet, but Shadow Lass uses her powers to distort the animals' sense. Colossal Boy and Shrinking Violet set up a surrogate beacon that attracts the creatures and leads them away from Imsk.
Five Year Gap/Threeboot
Imsk's history is modified for the "Five Year Gap" Legion stories. Never a prosperous planet, Braal their neighboring planet is devastated by the economic collapse of the United Planets. Braal enters into a war with Imsk, and is thrashed when the Imskians deploys a weapon which turns Braalian magnetic abilities against them, at the battle of Venado Bay. Those who get a partial dose are merely knocked out and lose their magnetic abilities. Those who get a full dose are torn apart by their own magnetic powers. After being defeated, Braal is occupied by Imsk, which keeps a sizable garrison on the planet to control it.
Following the second reboot of the Legion of Super-Heroes, the Imskians live in a globe on the desk of Brainiac 5, who saved the civilization from an undisclosed threat. Since planet Imsk is a microscopic world kept on Brainiac 5's desk the natives of Imsk worship Brainiac 5 as if he was a god. In this reboot the character Shrinking Violet a native of this world is fiercely loyal to Brainiac 5 for this reason. It is not clear if the natives shrink naturally, or as in earlier continuities, or if Brainiac's rescue involved the same technology used by his ancestor to shrink Kandor.