Rusty was Firestar's birth name. He was born to Nutmeg, his mother, and Jake, his father. He has a sister named Princess, too. Though he had the desire to become a clan cat, so he joined Thunderclan.
Shortly after Firepaw was named an apprentice, Graypaw became his best friend. Lionheart and Tigerclaw became his unofficial mentors. Ravenpaw was a sleek black apprentice of ThunderClan, with the mentor of Tigerclaw. Tigerclaw was hostile to all the apprentices. Ravenpaw came back from a recent battle at Sunningrocks with terrible news. Redtail, the ThunderClan deputy, was murdered, ans so was Oakheart, the RiverClan deputy. Bluestar was torn at the loss of her beloved deputy. Ravenpaw was injured, so Spottedleaf, the ThunderClan medicine cat, took care of him. Firepaw was a little bit in love with Spottedleaf, due to her beauty. Bluestar became Firepaw's mentor shortly after.
While he was out hunting, Firepaw ran into Yellowfang, ShadowClan's former medicine cat, driven out by Brokenstar, ShadowClan's heartless leader. Yellowfang is very hostile toward Firepaw, so he catches a rabbit and feeds Yellowfang, breaking the warrior code. He gets in trouble and his punishment is to care for grumpy old Yellowfang.
Later, Firepaw and Graypaw take Ravenpaw to Barley's farm. They met Barley while they were on a journey to the Moonstone. Tigerclaw had tried to kill Ravenpaw for knowing too much about Redtail's murder. Brokenstar attacks the ThunderClan camp, and steals two kits, Brackenkit and Cinderkit. Yellowfang was gone, so Bluestar sends Firepaw and Graypaw to find her. They went into ShadowClan's territory and found her, then drove out Brokenstar. Spottedleaf was murdered in cold blood by Clawface, one of Brokenstar's warriors. When Brokenstar was driven out, two of his warriors- Blackfoot and Clawface went into exile with him. Lionheart was also murdered. Ravenpaw witnesed what happened at the recent battle at Sunningrocks- that Tigerclaw was responsible for Redtail's death and not Oakheart. Oakheart died when rocks fell on him. After all this, Firepaw and Graypaw were named warriors- Fireheart and Graystripe.
Fireheart is now a warrior and has found a new enemy, Tigerclaw. Bluestar sends them out on their first warrior mission, to find WindClan and bring them home from exile. It was a tough journey, like a journey to Highstones. He and Graystripe found the WindClan cats, and brang them home. Bluestar is pleased, so she makes Brackenkit and Cinderkit apprentices. She gives them the names Brackenpaw and Cinderpaw. Fireheart was a mentor to Cinderpaw, and Graystripe was a mentor to Brackenpaw. Brackenpaw is the more quiet and obedient apprentice, which makes it easier for Graystripe and harder for Fireheart. Cinderpaw was the energetic type of cat, and Fireheart has a hard time concentrating on training. He recieves help from Whitestorm, a senior warrior of ThunderClan. Then Dustpaw, an apprentice of ThunderClan, came to Fireheart and said he had a message from Tigerclaw and told him he wanted Bluestar to meet him at the side of the Thunderpath. Fireheart said no, because Bluestar and some of the Clan were afflicted by greencough, a chest infection that cats could get in Winter. She would be too sick to travel that far. Then Cinderpaw offers to go tell Tigerclaw that Bluestar couldn't come, but Fireheart said it would be too dangerous for her. While Fireheart collects catnip for Bluestar under Yellowfang's command, Cinderpaw disobeys Fireheart's orders and goes to Tigerclaw. When Fireheart goes to bring the catnip back, he finds Cinderpaw lying motionless on the Thunderpath. She had been hit by a monster, and Tigerclaw was there and witnessed the whole thing.Cinderpaw is brought to Yellowfang's den and Yellowfang tells Fireheart she can never be a warrior with her crippled leg. Fireheart is heartbroken.
Later, after this, he goes out to hunt. He ended up running into sister, Princess. He goes and talks to her, and she gives him one of her kits so he could become a warrior. He takes him to ThunderClan, and he is named Cloudkit. Brindleface, one of ThunderClan's queens, offers to take care of him. Fireheart then suspects that Tigerclaw had laid a trap for Bluestar. Tigerclaw had become deputy.
Then, Fireheart, Sandpaw, and Brackenpaw see Graystripe fall into the river near the border of their clan. Silverstream, a RiverClan warrior, saves him and they fall in love with eachother, which is against the warrior code.
Brokenstar and his rouges attack the ThunderClan camp. Fireheart blinds Brokenstar, and kills Clawface. Brokenstar is named Brokentail and is kept prisoner of ThunderClan. WindClan and RiverClan are angry that Brokenstar is still alive, so they attack the ThunderClan camp. Brackenpaw was the one who warned the Clan about this, so after they won the battle, Brackenpaw becomes a warrior, and is given the name Brackenfur. Meanwhile, Silverstream is almost ready to give birth to Graystripe's kits. In a battle with WindClan and RiverClan, when Fireheart is going attack Silverstream, he lets her go without a scratch. Tigerclaw takes notice of this.Tigerclaw tells Bluestar about it, so she punishes Fireheart. Fireheart and Graystripe were also caught feeding RiverClan with prey from their own territory. They get punished.
Silverstream finally gives birth to Graystripe's kits, and dies doing so. Graystripe grieves for her all night. Meanwhile, Tigerclaw's treachery was discovered after he brought Brokentail's old allies to attack the camp. He attempted to kill Bluestar, but Fireheart tried to protect her and fought with him. He was then exiled by Bluestar in attemt for her life. The naming ceremony was late; Clan leaders must name a new deputy before moonhigh. Fireheart was named deputy. Bluestar goes to the Moonstone, and she takes Fireheart with her, but they are stopped by WindClan. A huge fire sweeps through the camp, and both Yellowfang and Patchpelt die during it. Fireheart saves Bramblekit's life, even though he was Tigerstar's son and could have used his the time to save Patchpelt.
Cinderpaw, who becomes the new medicine cat apprentice, is named Cinderpelt. During the fire, RiverClan offers shelter to ThunderClan while the rain puts out the fire. Bluestar loses control of herself after all of the tragedy, and declares war on StarClan. Bluestar tries to launch an attack on WindClan, but Fireheart stops her.
Afterwards, there is a wild dog pack in the forest. The dogs kill Swiftpaw, and they gravely injure Brightpaw, specifically injuring her face. When Brightpaw becomes a warrior, she is named Lostface by Bluestar to prove she was serious about declaring war on StarClan.
RiverClan tries to take Sunningrocks back, and two cats from riverclan, Mistyfoot and Stonefur, are furious with Bluestar. Graypool, Mistyfoot and Stonefur's foster mother, reveals that she was not their real mother. Bluestar was their real mother. Tigerclaw was there, watching, so he knew this. Later, Brindleface, Cloudtail's foster mother, was found dead even though the dogs did not kill her. It turns out that Tigerclaw had joined Shadowclan, and became their leader, Tigerstar. He had killed Brindleface and Runningwind to use as bait to lead the dogs to ThunderClan. Bluestar saw that Tigerstar was holding down Fireheart to let one of the dogs catch up to him, so she rammed into it and fell into the river. The dog mauled her while she was drowning.
After Mistyfoot and Stonefur pay their last respects to Bluestar, Fireheart goes with Cinderpelt to Mothermouth to recive his nine lives from StarClan. After that, he belives that his old enemy, Tigerclaw, has become a much greater threat then before. Fireheart, who had then became Firestar, has a hard time thinking of who should be the next deputy. Graystripe comes in his den, and tells him he can't be deputy. Firestar then chooses Whitestorm as deputy. Tawnypaw, an apprentice of ThunderClan, spits at Smallear, a ThunderClan elder. Tawnypaw, also Tigerstar's daughter, leaves ThunderClan and joins ShadowClan. Darkstripe is exiled from ThunderClan because he fed deathberries to Sorrelkit, a kit of ThunderClan.
Half-brothers: Socks Scourge/Tiny
Daughters: Leafpool Squirrelflight
Grandsons: Lionblaze and Jayfeather
Grandnieces: Ivypool, Dovewing
- Lionheart and Tigerclaw were his unofficial mentors
- The ShadowClan cat that was watching him, Ravenpaw, Graypaw, Lionheart and Tigerclaw, in the first book, may have been Clawface
- Bluestar was his actual mentor while Lionheart and Tigerclaw were just co-mentoring him with their own apprentices. This is the only time a cat does not get a mentor after the apprentice naming ceremony.
- He may be based on a cat Kate knew.
- The Erins believed that after the first arc, Firestar's story was pretty much over, so they started the next arc from a fresh viewpoint.
- Firestar's love relationship with Spottedleaf was never shown that often when she was alive because he was only a new apprentice at the time. There probably wouldn't have been more relationship if she lived because medicine cats can't have mates.
- Firestar's mother, Nutmeg, probably does not know about him becoming a wild cat.
- He has never had feelings for Cinderpelt.
- It was confirmed he's not related to the ThunderClan founder, Thunder.
- In an Erin Hunter Chat, it is revealed that Scourge and Firestar share the same father, Jake. In the same chat, it is also revealed that he loses a life helping Ravenpaw and Barley.
- He was mistakenly called Firepaw despite already having received his warrior name.
- In the beginning of The Darkest Hour, he is mistakenly called Firestar before receiving his leader name.
- He is mistakenly called Fireheart after receiving his leader name.
- He has been mistakenly depicted with amber eyes on several occasions.
- He has been mistakenly described as golden.
- He has been mistakenly called Firestorm.
- Tigerstar was mistakenly called Firestar once.
- He is mentioned to have seven lives, however at the time he only had five.
- One of Leafstar's kits, Firekit, is named after him.
- Fireheart was said to be the deputy after Lionheart died in The Elders' Concern, even though Tigerclaw became deputy after Lionheart.
- Kate stated that Firestar was not killed by the burning tree, but instead died of his wounds from the battle. Dovewing only imagined she saw him get up and walk away, and the lightning striking the tree snapped her back into reality.
- In Dawn, he is mistakenly described as dark red.
- Although Firestar is confirmed to be on both the cover of Into the Wild and The Last Hope, it can be noted that his design is drastically changed on the latter cover, now sporting white markings on his muzzle and around his eyes along with dark brown stripes and ears.