Sasuke is the youngest boy of Fugaku Uchiha and Mikoto. Apart from being the captain of police his dad Fugaku was also the head of the Uchiha clan to which Sasuke belongs.
Similar to any other family where the youngest son is nearly always looking up to his older brother, Sasuke learnt to grow up in his brother’s, Itachi, shadows.
To make matters worse, Itachi was always seen as the special one by both the members of his clan and people from the village. Although he tried hard to shine, Sasuke quickly realised that his accomplishments were only measured to those of this brother’s even by his own father.
As the years went by, the rivalry between the two brothers grew and this was acknowledged by his elder brother when he compared himself to a wall which Sauke had to climb over to get any recognition.
Fortunately for Sasuke, Itachi’s behaviour began to change for the worse which brought his father closer to him and away from Itachi.
It was his father that taught him the great Fireball Technique which is seen as a rite of passage within the Uchiha clan. However when Sasuke tried to perform it for the first time, the results were less than impressive resulting in his father mentioning that his elder brother was able to accomplish the same feat on his first attempt.
This served as great motivation for Sasuke and after practising hard for only a week, he was able to perform the technique in front of his father. This finally gave him the recognition that he had long for. He could now stand tall and out of his brother’s shadows.
As a reward, his father allowed him to wear the clan’s emblem on his back and warned him not to follow in Itachi’s footsteps.
Things got out of hand when one night, all the members except for Sasuke were slain by Itachi in a feat of rage. Sasuke also learnt that the reason why his brother did not kill him was because he was according to him, not even worth killing.
Itachi also mentioned that he knew that his actions on that night will make Sasuke hate him enough to want to kill him. He also revealed the secret location where the clan would meet and what he should do to awaken his Mangekyou Sharingan.
As far as he can recall, Sasuke’s recollection of events that night are a bit blurry but he later remembered that he found out how to finally awaken his Sharingan and pursue Itachi. After killing his brother, Sasuke learnt that Itachi was under strict orders from the Konoha Elders to murder his own clan members and that he in fact loved his younger brother. This resulted in Sasuke vowing never to stop until the Elders and their last child had been destroyed.