He was born on Vulcan at a time when the philosopher Surak began preaching his philosophy of peace and logic. S'task eventually met him, and sought to become his student, though he was refused at first before finally being accepted. As peace and logic began to spread on their world, the planet was visited by visitors from the Orion race. Surak was intended to meet them at ShiKahr, but was detained at a port facility whilst S'task met them.
Rather than being benevolent visitors, the aliens captured all the representatives, and took them to their orbiting slave-ships. S'task attempted to preach peace to them, but was eventually forced to use his talents and psychic arts to kill his captors and escape to the surface of Vulcan after inciting a riot on the slave-ships among the captured Vulcans. These encounters changed S'task's opinion and theology, which was traced to his capture by Orions in 22 BC.
After the Ahkh-era ended with the invaders driven out, the divide between S'task and his mentor increased, due to their different beliefs. Eventually, S'task decided to leave his home world and journey to the stars in search for a new planet. Taking eighty thousand followers, they prepared to leave the motherworld behind in search for a new beginning. S'task's poem, Last Song, was the second-most-translated poem on Vulcan at the time.
Before he departed aboard the Vulcan starship Rea's Helm, he was met by a figure at the docks – his former mentor, who carried three swords made by the smith S'harien, with Surak asking his former student to take care of them on the journey, which began the Vulcan-in-Exile. Over the course of the long voyage, two swords were lost in the flight, whilst a single one was placed in a chair in the Exile Council-chambers.
Whilst journeying through space, a mutated strain of diseases erupted among the fleet, which was responsible for claiming S'task's wife and children. S'task himself almost succumbed to death, but managed to survive. He would also grow bitter over the years at the thought of him and his comrades dying in the cold of space. He would, however, be one of the few leaders who managed to reach a new home world, one that would eventually become known as Romulus. Upon arrival at his new home, S'task laid the cornerstone of the Romulan Senate building, a structure that withstood the test of time in later eras. (TOS novel: The Romulan Way; TOS - Vulcan's Soul novel: Exiles)
He later cared for Solor, the son of Karatek who had been banished to Remus where they were made to work by dominant members within Romulan politics. Seemingly fatally wounded during this particular incident, he helped the young Solor and returned him to his family, but was incapable of ending Karatek's exile. (TOS - Vulcan's Soul novel: Epiphany)
Subsequently, by right, he attended the meetings of the Grand Council on Romulus. He bore witness to the rise of the T'Rehu, who sought complete control over the Council, but S'task simply departed the chambers without asking leave from her. During the second meeting with her, he did so once again, and did not respond to T'Rehu's order to halt, which led to her commanding her guards to end S'task's life. Thus, he was murdered at the age of 248 on the floor of the very Romulan Senate that he'd helped to build, by the mad "Ruling Queen."
T'Rehu, who felt threatened by S'task's standing and his opposition to her plans of dominion. Many Romulans attended her coronation despite the fact that she was S'task's murderer – this was because his influence and power waned over the years after the settlement of Romulus, leading to the thought that they believed he was necessary only during the journey through space. (TOS novel: The Romulan Way)
In an alternate timeline – one where Surak died as a young man and never got the chance to spread his philosophy of peace, and where the Romulan/Vulcan schism never took place. However, the teachings of S'task had become lost to the Vulcan people, who degenerated into brutal savages who constantly warred with one another. The katra of S'task, preserved in the mind of one of his loyal followers – S'oval – eventually helped bring about a reformation to his people, promising a way to contain and direct the passions and emotions of the "Minsharans" (as the Vulcans of that timeline were called). (ST - Myriad Universes novel: The Tears of Eridanus)
- "I am Vulcan, bred to peace." (TOS novel: The Romulan Way)
- "When people think an idea is theirs, they take it so much the more to heart than if they think they got it from someone else, or worse, followed a great public trend. There is nothing people want to do more than to follow great trends, and nothing they want less to seem to be doing." (TOS novel: The Romulan Way)
- "You may do so. That is the prerogative of force. But I give no honor to force. Powers, yes. But you have no power, none that I recognize. I ask no leave of you." – S'task to T'Rehu, who said she would kill him (TOS novel: The Romulan Way)
- "The beginning is contaminated, and force will not avail you, or it." – S'task to T'Rehu (TOS novel: The Romulan Way)