A native of the world Dac, the Mon Calamari race is aquatic by nature, spending much of their time below the surface of their watery homeworld. They share their planet with the Quarren, Whaladons and the Moappa. The species claims that their race evolved near the islands of Mkuto, which are considered sacred by the entire Mon Calamari society. Their ancestors were land dwellers, however, they have always shown an affinity towards the water and aquatic life, and fed mostly on crustaceans, fish and fruit. Over time, they developed an early form of their current aquaculture which enabled to farm both fish and kelp. Unlike the other species on Dac, the Mon Calamari civilization was centered in the shallower portions of the ocean and on the few available islands. This allowed them to have a technological head start on their neighbors, including the Quarren who lived in the depths of the oceans. Despite this advantage, their progress was still considerably slower than humans, due to a lack of harder metals on Dac.

Around 4,500 BBY, the Quarren attacked the Mon Calamari, inciting the Quarren Wars. The Mon Calamari, though significantly less aggressive than their cousins, had considerably better technology, and were able to stave off the attacks, and win the war. In order to prevent the reoccurrence, the Mon Calamari took hundreds of young Quarren as prisoners, taught them the Mon Calamari culture and then set them free. These reeducated Quarren eventually became the heads of their own society and a peace blossomed which lasted for centuries, though it was tense at times. After the initial missteps between the two species had passed,  the Mon Calamari and Quarren settled into a symbiotic relationship with one another, allowing a golden age of prosperity to engulf their world. As the Mon Calamari continued to advance technologically, the Quarren benefited, and together began to create floating cities which would hold their place of planetary government, learning and culture.

Having always been explorers of their own world, the Mon Calamari set their sights on exploring the stars, and along with their Quarren partners, created a program for their slow expansion into space. This undertaking began with the creation of a ring of habitats and laboratories which they used to further their mission along. Over a century passed until they had developed their understanding of zero-gravity and propulsion, this led to the next steps in their journey. This followed by early star liners being launched to nearby worlds for colonization. The planets Mantan and Ruisto were among the first.

During their expansion into the galaxy, the Mon Calamari made first contact with the Republic, just prior to the Great Sith War, in 4,166. Their eagerness to learn more about the vast Republic caused them to become somewhat estranged from their Quarren cousins, who were much more cautious and untrusting. Due to this, the Mon Calamari and their homeworld remained a mystery to the Republic, as the government of Mon Calamari and Quarren refused to accept anything more than a “keep in touch” relationship due to the Republic’s almost constant state of war over the centuries. Later however, Dac did join the Republic, and in the time of the Sacking of Coruscant, the current Chancellor of the Republic was in fact a Mon Calamari.