It is generally believed to have happened in 1162, but the exact date is uncertain.
Here's what we know:
* The event: The Serbian Grand Prince Stefan Nemanja, founder of the Nemanjić dynasty, ordered the execution of several high-ranking Serbian noblemen, including his own brother, Tihomir.
* The reason: The motives behind the executions are debated. Some sources claim Tihomir was plotting against Stefan Nemanja and his family, while others suggest it was a power struggle for the throne.
* Significance: The Slaughter of the Knezes marked a turning point in Serbian history, consolidating the power of the Nemanjić dynasty and paving the way for a period of strong and centralized rule.
While the exact date is not definitively established, the historical consensus points to 1162.