The Mon Calamari people are a humanoid, aquatic species with high-domed heads, webbed hands and large, goggle-like eyes. They hail from the oceans of Mon Cala, a planet they share with the Quarren. During the Clone Wars, differences between the two cultures were fanned by Separatist troublemakers to erupt in civil war. During the Galactic Civil War, the Mon Calamari were said to be the soul of the Rebel Alliance. The Empire pressed these gentle, amphibious people into war by subjugating their watery world. In retaliation, the Mon Calamari became one of the key species of the Rebellion, supplying badly needed warships to the outnumbered Alliance fleet.

A veteran commander, Ackbar led the defense of his homeworld, Mon Cala, during the Clone Wars and then masterminded the rebel attack on the second Death Star at the Battle of Endor. Ackbar realized the rebels had been drawn into a trap at Endor, but adjusted, with his fleet buying valuable time for the attack to succeed. After the Battle of Endor, Ackbar became a Grand Admiral in the New Republic, winning many victories including the pivotal Battle of Jakku. He retired to Mon Cala, but was coaxed back into service with the Resistance by Leia Organa.

The heir to the throne of Mon Calamari during the Clone Wars, Prince Lee-Char carried the burdens of his home world following the assassination of his father, King Yos Kolina. Separatist agitators began stirring up the undercurrents of hostility between the Mon Calamari and the Quarren, pushing the planet towards civil war. Despite his inexperience, Lee-Char longed to unite his people, but could not find the way. Surrounded by wise advisors, Lee-Char concentrated on survival as war erupted in the oceans of Mon Cala. But he did not give up hope in unifying the planet in resisting the Separatists.

A ravenous Karkarodon, Riff Tamson was a ruthless Separatist commander placed in charge of operations on the water world of Mon Cala. Count Dooku tasked him to disrupt the fragile peace between the Mon Calamari and the Quarren. Though present on the planet as a Separatist envoy, he secretly conspired with Quarren chieftain Nossor Ri to bring the Quarren into the war on the side of the Confederacy. Though Nossor believed he was doing what was best for his people, he had no idea of the true extent of Tamson's wicked plans.

Quarren, or "Squid Heads" as they are sometimes rudely called, are an alien species characterized by the four tentacles that protrude from their jaws. They have deep turquoise eyes, and each hand is capped with finned or suction-cup tipped fingers. They are capable swimmers, and like the squids they resemble, they are able to spit out clouds of ink as a defensive measure. Quarren hail from the planet Mon Cala, a world they share with the Mon Calamari. During the Clone Wars, the Separatists backed a Quarren insurrection that plunged the planet into civil war.

The watery world of Mon Cala was the site of a civil war during the Clone Wars, as the Mon Calamari people sided with the Republic, while the Quarren were backed by the Separatist Alliance. Senator Meena Tills was caught in the midst of this conflict, advising where she could while under the protection of the Jedi and clone troopers. Later, Senator Tills was part of the Delegation of 2,000 -- Senatorial representatives concerned with the manner in which Chancellor Palpatine had waged the Clone Wars. The Petition of 2,000 identified Senators formally complaining on Palpatine's conduct, and requested that he return his emergency powers to the Senate following the resolution of the conflict.