The Stromma were a resolute and determined sentient species that originated from the planet [Oristrom], situated within the Unknown Regions of the galaxy.
In their early years, specifically during what they called the Expansion Period, the Stromma found themselves in conflict with the insectoid [Quesoth] species. After being defeated, the Stromma evolved into strong allies of the Quesoth. Later, Oristrom fell under the control of the alien warlord [Nuso Esva]'s forces, but Grand Admiral Thrawn and the Empire of the Hand eventually ousted Esva from the planet. Following their liberation, the Stromma forged an alliance with the Empire of the Hand, with some Stromma individuals joining the Imperial ranks aboard the Star Destroyer Admonitor. Nevertheless, in 8 ABY, the Stromma emissary Nyama commanded all Stromma serving on the Admonitor to resign from the Imperial military and disembark from the Star Destroyer, driven by his conviction that the Imperials would suffer defeat in an upcoming attack against Esva's forces on the planet Quethold.