This is where the fault lines collide. Listen to the planet's heartbeat. Breathe slowly, and calm your mind. Let memories return to you. Memories shape time. Time overlaps. The overlap becomes our memory. Memories construct time. History repeats itself. We must stand in its flow and understand the world. Such is the goal of our tribe.
- —Eidolon Wall in Madain Sari
Summoners (召喚士, Shōkanshi?) are a race of horned human-like people in Final Fantasy IX. Their home is the city of Madain Sari in the Outer Continent. Their special power is the ability to summon eidolons, immensely powerful monsters that serve the summoner. With eidolons, summoners have enough power to destroy whole cities. Physically, summoners are no different from normal humans, except for a small horn on the top of the forehead.
Hundreds of years ago the summoners lived on the Mist Continent with the other peoples. During a failed summoning experiment, the eidolon Alexander went berserk. To stop Alexander from ever being summoned again, the summoners divided its summoning gem into four fragments and left three pieces with the three nations on the Mist Continent. They took the final gem fragment with themselves to Madain Sari, a town they established on the Outer Continent, where they dedicated their lives to researching summon magic. The Final Fantasy IX Ultimania explains that Madain Sari was chosen as the location of the village because it is a place where the world's pulse concentrates.
The summoners lived peacefully in their new homeland until the arrival of Garland on Gaia. Rather than using their powers to dominate other races, the summoners' main preoccupation was to study the nature of eidolons and much of their work is seen on the eidolon wall in Madain Sari. Seeing the summoners' powers as a threat to his plans, Garland sent the Invincible to destroy Madain Sari, along with most of the summoner population.
The only known survivors were a girl named Sarah, her mother Jane, and Eiko's parents and grandfather. Eiko was born four years after Madain Sari's destruction; her parents died when she was young, leaving her with her grandfather, until he died. Eiko survived in the ruins of Madain Sari with the help of moogles.
Sarah's mother died after bringing her daughter to Alexandria, and the girl was raised by the kingdom's royal family as "Princess Garnet": the real, seemingly identical princess had died shortly beforehand. Without anyone to teach her the ways of summoning, and with her horn removed, Garnet had no idea she was any different from the people around her.
Garnet's powers are awakened when her adoptive mother, Queen Brahne, steals her eidolons using a sinister magic. Meeting with Eiko, Garnet learns of her summoner heritage, while she watches her deranged mother use her eidolons for world conquest.
Kuja, the queen's manipulator, uses Brahne's ambition to attempt to steal Alexander by gathering the four gems. He destroys Brahne by using one of her stolen eidolons, Bahamut, against her, then moves to attack Alexandria. Garnet and Eiko work together to summon Alexander to stop Kuja's attack and continue to fight alongside the other party members to defeat Kuja and finally save the world. After Kuja's threat has been removed, Garnet and Eiko are alive and well, showing that the summoner legacy will most likely live on.