Deidara was a Missing-nin from Iwagakure and and one of Akatsuki's most powerful members. He was the partner of Sasori until the latter's death, and then the partner of Obito Uchiha until his own.
Deidara was born in the village of Iwagakure and during his time there as a shinobi, he was the student of Onoki, the Third Tsuchikage. As Deidara was a holder of the Explosion Release kekkei genkai, he was able to become a member of the Explosions Corps, and though his clay scultures were praised, Deidara felt their were less than perfection and stole a kinjutsu which allowed him to creat his explosive clay, which he used in his attempt to flee the village by killing his pursuers(the anime also showed that he destroyed several building in Iwagakure at this time as well). Afterwards, he became an S-rank missing-nin, who wandered the world and offered his services as a bomber to various countries. His exploits eventually attracted the attention of Akatsuki, an organization comprised mostly of S-rank missing-nin, of whome Deidara met with three members. One of these members, Itachi Uchiha, Deidara agreed to fight under the condition that he be left alone if he won. Deidara, however, wasd easily defeated by Itachi, due to his Sharingan, which Deidara grew to hate, as well as Itachi. Deidara joined the organization, but spent the rest of his life preparing for revenge against Itachi by training his left eye to counter the Sharingan's genjutsu and creating his C4 technique specially for killing the Uchiha.
Deidara made his debut in part 2 of the series, where he was first seen travelling to Sunagakure with his partner, Sasori, their objective being to capture the Fifth Kazekage, Gaara, who was the jinchuriki of Shukaku, the One-Tailed Beast. Deidara infiltrated the village by the sky and took out the lookouts, before finding himself, to his surprise, confronted by Gaara, who attacked him with his sand and drove him a distance away. Deidara proceeded to battle Gaara with his explosive clay, which proved not to be stronger than Gaara's Absolute Defense, which allowed him to trap Deidara in a giant sand sphere which he escaped by sacrificing his ride and fled on another. Gaara grabbed his left arm and crushed it, forcing Deidara to amputate what was left to break free again. Acknowledging Gaara's might and that he had underestimated him, Deidara created his C3 technique and dropped it on Sunagakure, forcing Gaara to use his remaining chakra to shield it. Deidara detonated another explosive close to Gaara, forcing his sand to defend him, and detonated more within it to shatter Gaara's sheltering sphere, which crumbled. As Gaara began to move his sand back to the desert, Deidara allowed him to do so, capturing him after he fell unconscious. Though Kankuro, Gaara's brother, attempted to stop them, they reached the Akatsuki's hideout, where the entire group extracted Shukaku from within Gaara, before they waited for the arrival of Gaara's rescuers, one of which was Naruto Uzumaki, another jinchuriki and a friend of Gaara's, who Deidara tactfully indentified by sitting on Gaara's chest to anger him.
Deidata took Gaara's body and fled with it, leaving Sasori to deal with his grandmother and Sakura Haruno, while Naruto and Kakashi Hatake followed him. Deidara attempted to throw Kakashi off, but failed and the latter used his Mangekyo Sharingan to tear off his remaining arm, giving Naruto a chance to disable Deidara's ride and knock him into the forest, where he could retrieve. Deidara managed to evade Naruto with a clay clone, but was surprised to see Chiyo and Sakura arrive, having defeated Sasori. As he attempted to leave, he was cornered by Team Guy, lead by Might Guy, all of whom Deidara held off. He made his way to his clay bird, and swallowed some of his clay, which he seemingly used to blow himself up and commit suicide, but in reality it was just a clone, and Deidara tunnelled underground to escape. Later, he regrouped with other members of the Akatuki, and recovered his arm, which was later sewed back on by Kakuzu, another Akatsuki member. Deidara received Obito Uchiha, under the guise of Tobi, who Deidara went on to capture the Three-Tails, Isobu, with and, after it was sealed, he and Obito went after Sasuke Uchiha, who Deidara wanted to kill for depriving him of the opportunity of killing Orochimaru. Deidara used C1 against Sasuke initially, but ended up using C2 to create a giant dragon and landmines.
Deidara tricked Sasuke and caught him off guard with this, forcing him to utilize his Cursed Seal's second stage. Sasuke managed to destroy the C2 and nearly kill Deidara by pinning him to it as it fell on the mines, but he survived and created his C4, which he planned to use against Itachi Uchiha, Sasuke's brother. Though the technique seemingly killed Sasuke, it was only genjutsu, and Deidara was stabbed through from behind by him using Chidori. However, he saw through the illusion and switched with a clay clone beforehand, trapping Sasuke within another C4. When he detonated, Sasuke again seemed to perish, but was again just genjutsu as Sasuke deactivated the inhaled mini bombs with his Lightning Release and punched Deidara from behind. Deidara attacked Sasuke again and he collapsed after countering the attack. Deidara became enraged when Sasuke then deactivated his Sharingan and utilized his C0 technique, his strongest explosive of all, turning himself into a living bomb and detonating himself in a final attempt to kill Sasuke and prove his art superior to the Sharingan. Sasuke was outclassed by this and summon Manda, a giant snake to save himself, making Deidara's death pointless.
Deidara was later revived by Kabuto Yakushi, along with all the other deceased Akatsuki members, as a military weapon for Akatsuki's side. Deidara was forced by Kabuto to assist him in his pursuit of Naruto Uzumaki and Killer B, the only remaining jinchuriki, but they were intercepted by Onoki, the Third Tsuchikage and Deidara's teacher, who Kabuto got punched by. However, they were both revealed to be clay clones, which explosed, but Onoki was revealed to be likewise a clone by Akatsuchi, one of Onoki accompanying bodyguards. While Kabuto forced him to head for the Island Turtle, which was the holding place for the jinchuriki, Deidara still ended up fighting Onoki and his men. Akatsuchi blocked his explosives with his Rock golem and Deidara was drawn away from the Island Turtle, where he challenged Onoki and his Dust Release with his explosive clay, but was forced back into his coffin by Kabuto before the fight could progress any. Later, Deidara was tasked with using his explosives for disrupting members of the Allied Shinobi Forces after the Fourth Shinobi World War came to a start.
Deidara and his team took Muta Aburame captive, and Deidara planted some of his explosives in his jar, before Sasori controlled him to attack the opposing Surprise Attack Division. Deidara then detonated the explosives, killing Muta, but the division evaded the attack. Deidara attacked them personally, noting that he and his group couldn't lose as they were immortal. The division turned the tables slightly, colliding Deidara with Sasori. He detonated more clay that he had inside Shin, another revived shinobi, which was smothered by Kankuro, to Deidara's displeasure. Deidara proked Sai, Sasuke's replacement on Team Seven, saying that he was a weakling incapable of replacing Sasuke and that his friend Shin was "the bomb", ridiculing Sai's art as well. Both he and Sasori are then struck from behind by Sai, and caught in Kankuro's puppets. Prepraing to use C0 again, Deidara was countered by Omoi, Killer B's student, who stabbed a lightning-infused sword into his chest, defusing the clay. Later, reinforcements arrive, but do nothing to recue Deidara, who was secured by the Samurai after their arrival. Later, after the release of the Impure World Reincarnation, Deidara, while threatening to blow up again, was sent back into the afterlife, along with all the other revived shinobi besides Madara Uchiha.
Deidara was a very short-tempered individual, with a sadistic, battle-loving nature. He enjoyed a good fight, and bore an intense hatred for the Sharingan, which he first encountered in his battle with Itachi Uchiha, who Deidara hated even more. This hate extended to his younger brother, Sasuke Uchiha, during their battle. Deidara loved art and would respect any form of it, though he felt his art(his explosive clay and bombs) to be superior to all else and was unwilling to believe that anything could ever defeat it. Deidara's relationships with his fellow Akatsuki was sometimes neutral, except for Itachi. He did, however, show respect for Akatsuki's leader, Pain, as did the rest of the organization. His two partners, Deidara got along with fairly well, with his first partner, Sasori, being very respected by Deidara as a fellow artist. His second partner, Obito Uchiha, due to his constant behavior under his comical false persona, Deidara became annoyed with sometimes, but he had a sense of appreciation for him, as he apologized to his partner for his mean actions towards him in his thoughts, before initiating his suicide bomb technique.
Deidara was a very powerful and dangerous S-rank Missing-nin, who skills were great enough to catch the eye of the Akatsuki, who wanted him in their group. Akatsuki's leader, Pain, praised Deidara and, when he died, said that his death was a huge loss to the group. Deidara was able to single-handedly fight and defeat the much more powerful Gaara one-on-one and fight on even terms with Sasuke Uchiha, a prodigy of the Uchiha clan, despite the latter's mastery of the Sharingan and Lightning Release, which was Deidara's weakness, in a fight that originally ended as a stalemate, in the end outclassing Sasuke, who only accepted victory in their battle reluctantly. Deidara's teacher was Onoki, the Third Tsuchikage, who was proud of him, despite his annoying habit of fighting at a distance. Deidara's fighting style being long-ranged, his only mortal enemy was another long-range fighter.
Deidara's main weapon was his Explosion Release, which he had as a member of Iwagakure Explosions Corps. He stole a kinjutsu from Iwagakure before he left, which allowed him to develope mouths on his hands and chest, which he used to infuse clay with his explosive chakra to create his Explosive Clay, which he would mold into scultures that could explode at varying intensities on his will and that he could also use for transportation. Deidara's C1 was his weakest attack, but still kill-capable at close range. C2 employed Deidara creating a giant dragon and landmines, which Deidara's partner, Obito Uchiha, would plant in the ground around the battlefield, allowing Deidara to make pinpoint attacks with guided missiles from the sky and double the chances of hitting his target. C3 was one Deidara's most powerful attacks that, had Gaara not shielded it, would have destroyed the entirety of Sunagakure. C4, Deidara's second strongest technique, he created to kill Itachi Uchiha. It employed him creating a giant clone of himself that could explode into nano bombs too small to see with the naked eye and that would be inhaled by his opponents, who would be blown to pieces from within when he detonated the bombs. Deidara's strongest technique was his C0, which he would prepare by exposing a mouth on his chest that would be fed a large ball a clay, allowing Deidara to turn himself into a suicide bomb capable of a blast radius of ten kilometers in all directions from its point of origin. Using this technique, Deidara outclassed Sasuke, who was forced to summon a giant snake to escape death and claim a reluctant victory.
Another strong point of Deidara's was his intelligence, which showed in his use of tricks, misdirection and calculated gambles to get an edge over his opponents. This, more prominently that his clay, was crucial in his defeat of Gaara. He also managed to fool Sasuke Uchiha a couple of times during their fight, catching him off-guard with his C2 and nearly blowing his leg off and trapping him in his C4 via use of a clay clone to fool Sasuke. He also trained himself to see through genjutsu with his left eye after his first encounter with Itachi, and could use it for telescopic vision at a distance during the Fourth Shinobi World War. Deidara had great physical strength, despite being a long-range fighter, able to free himself from Gaara's sand and sever the remainder of his left arm at the same time.