Our Gemara brings a passage in II Shmuel (1:11-12) that describes King David’s reaction to the news that King Saul and his son Yehonatan had been killed and that the army of the Jewish people had been defeated. From the fact that David and his men tore their clothes, mourned and fasted, the Sages deduce that one is obligated in keriya (tearing one’s clothes) over the Nasi (King Saul), the Av Bet Din (Yehonatan), and news of tragedy (the Jewish people who lost the war).
The Gemara questions whether one is truly obligated to tear keriya over tragic news, citing Shmu’el’s lack of reaction to the news that the Persian king, Shevor Malka (Shapur I) had killed 12,000 Jews in Kayseri (in what is now modern-day Turkey). The Gemara explains that keriya is not an obligatory response to every case of tragedy – only to situations similar to that of King Saul, when the tragedy represented the defeat of the Jewish people.
Yet the Gemara relates that King Shevor Malka had stated to Shmu’el that he had never killed a single Jew! The explanation presented by the Gemara is that those Jews were killed when the revolution in which they participated was put down by Shevor Malka’s troops; they were not killed as Jews.
King Shevor Malka, the Persian king who ruled from 241-272, was actually the founder of the great Sassanid Empire that fought against the Romans. Eventually he succeeded in extending his rule as far west as Syria and Anatolia. It appears that the Kayseri mentioned in the Gemara was an important city in Anatolia, and the revolt against the king, in which the local Jews participated, threatened his rule. He therefore put down the rebellion with an iron fist and killed many of the revolutionaries – including thousands of Jews. Generally speaking, however, Shevor Malka was known as a king who was a friend of the Jews under his rule, and he had a close relationship with the Shmuel.