Ranesh was born in Where Waters Meet, a village in the west of Deltora. When the village was plundered by pirates, Ranesh was orphaned and the village was destroyed. Ranesh fled the village and found work on a boat that carried passengers along the River Tor.
Eventually the boat was captured by pirates, who robbed and killed the passengers. They captured Ranesh and the captain of the ship and took them to a cave on the coast. The pirates threw the captain into a hole that led into the Maze of the Beast, then lowered Ranesh in by a rope so he could watch the Glus kill the Captain. The Pirates then forced him to work for them, threatening to feed him to the Glus if he refused.
A year later, Ranesh escaped from the pirates during a battle with a rival crew and traveled east. During his travels he stumbled upon the Valley of the Lost. There he met the Guardian, a powerful magician. The Guardian showed Ranesh a magnificent palace made of glass, and challenged him to play a game of skill. If Ranesh won, he would receive a casket of gold. If he lost, he was doomed to stay in the Valley forever. Ranesh refused to play the game; he valued freedom more highly than gold.
To his surprise, the wizard smiled and said that it would have been pleasant to defeat Ranesh, but that he did not need his company. He would have many other subjects soon, he had been told by his master. Ranesh ran from the Valley, and shuddered at wondering who the Guardian's subjects would be.
Ranesh made his way to the city of Del, where he lived as a thief. It was here he met Josef, the former palace librarian and guardian of the Deltora Annals. Josef taught Ranesh to read and write, and in return Ranesh told Josef of the Guardian and the Glus so that Josef could add them to his Deltora Book of Monsters. The two ended up growing close, with Ranesh viewing Josef as a fatherly figure. The pair eventually took up residence in the cellar of a pottery run by Mikal. The people of the pottery cared for them until they were taken to the Shadowlands. Ranesh and Josef spent the rest of the Shadow Lord's tyranny hidden in the pottery cellar, during which Ranesh returned to thieving to keep them alive.
After the Shadow Lord's defeat, Josef sent Ranesh to inform King Lief of the Deltora Annals, hoping the young king would come to him. Ranesh waited at the palace for an audience with Queen Sharn, where he spotted Jasmine heading to the forge. He followed her and introduced himself. At first Jasmine was skeptical, but Ranesh convinced her to follow him to the pottery by promising her his master's treasure, which were the Deltora Annals. Jasmine eventually agreed to bring the two of them back to the palace, where Josef was met with open arms and swiftly returned to his position as palace librarian, with Ranesh as his assistant.
During his stay in the palace, Ranesh met Marilen, a Toran girl rumoured to be Lief`s bride. She frequently visited the library and grew close to Ranesh. Josef noticed their budding affection and decided to send Ranesh off on some errands, hoping that, by the time he returned, Lief would be back as well.
Ranesh married Marilen sometime before the Full Moon Meeting and went to live with her in Tora. This forced Josef to hire a woman named Paff as his new assistant. Josef frequently wrote to Ranesh about her mishaps, and while Ranesh wanted to help his foster father, he learned that Marilen was pregnant and remained by her side.
Ranesh was part of the group who found Lief and Barda in the Dreaming Dunes, along with Jasmine, Zeean, and Manus. He confessed to Lief that, while he loved Marilen deeply, he could not stand how perfect everything was in Tora.
When the Toran Plague arrived in Del, Ranesh quickly returned to the city. He went to check on Josef, who died in his arms, calling Ranesh his son in all but blood.
Grief-stricken, Ranesh dressed Josef in his finest tunic and brought his body to the palace chapel. There he stood vigil over Josef's body, and so missed Lief's meeting where he told everyone that the Toran Plague was poison. When Lief began to doubt his judgement, he sought out Ranesh to ask him to deliver a letter to Marilen telling her to come to Del and claim the Belt of Deltora should he die.
When Lief learned that Ranesh spoke to Josef, he tried to ask him what he learned. Ranesh snapped at this invasion of privacy, but when Lief told him it was to try and find the location of the Sister of the South, he quickly apologised and left at once to retrieve Marilen. He returned just after Lief and Fidelis destroyed the Sister of the South, along with food that Marilen brought with her from Tora. He also presented Lief with Josef's last book, Tales of Deltora.
On Lief's request, Ranesh inspected Josef's tunic, and discovered a map of Deltora that marked the city of Hira. Lief, Barda, and Jasmine rushed to the city on the back of Fidelis while Ranesh travelled with Doom, Steven, Lindal, and Gers. They arrived in time to watch the seven dragons destroy the grey tide.
He and Marilen attended the wedding of Lief and Jasmine. Later, when Doom left to stretch his mind across Deltora, Ranesh took over his position as Lief's adviser. He and Marilen moved into the palace, where she took over as Palace Librarian. She also gave birth to a son, whom they named Josef.
Ranesh is described as being tall, lean and strong. He has dark brown skin and long, straight black hair, tied back in a band. He has clear hazel eyes and is described as being clever-faced. Ranesh's face is unlined and Jasmine thought that it was hard to tell what age he might be.