Simon Thassi
An imaginary depiction of Simon Thassi from Guillaume Rouillé's Promptuarii Iconum Insigniorum (1553)
Leader of the Maccabees
Reign	142–135 BC
Predecessor	Jonathan Apphus
Successor	John Hyrcanus
Prince of Judaea
Successor	John Hyrcanus
High Priest of Judaea
Predecessor	Jonathan Apphus
Successor	John Hyrcanus
Died	135 BC Dok
Issue	John Hyrcanus Mattathias II Judas II
Dynasty	Hasmonean
Father	Mattathias
Religion	Hellenistic Judaism

Simon Thassi (Hebrew: שִׁמְעוֹן הַתַּסִּי‎ Šīməʿōn haTassī; died 135 BC)^[1] was the second son of Mattathias and thus a member of the Hasmonean family.

The name "Thassi" has a connotation of "the Wise", a title which can also mean "the Director", "the Guide", "the Man of Counsel", and "the Zealous".^[2][3] This Simon is also sometimes distinguished as Simon the Hasmonean, Simon Maccabee, or (from Latin) Simon Maccabeus.

Simon took a prominent part in the Jewish revolt against the Seleucid Empire led by his brothers, Judas Maccabaeus and Jonathan Apphus. The successes of the Jews rendered it expedient for the Seleucid leaders in Syria to show them special favour. Therefore, Antiochus VI appointed Simon strategus, or military commander, of the coastal region stretching from the Ladder of Tyre to Egypt. As strategus, Simon gained control of the cities of Beth-zur and Joppa, garrisoning them with Jewish troops, and built the fortress of Adida.^[4]

After the capture of Jonathan by the Seleucid general Diodotus Tryphon, Simon was elected leader by the people, assembled at Jerusalem. He at once completed the fortification of the capital, and made Joppa secure.^[5][6]

At Hadid he blocked the advance of Tryphon, who was attempting to enter the country and seize the throne of Syria. Realizing he could gain nothing by force, Tryphon demanded a ransom for Jonathan and for the release of Jonathan's sons as hostages. Although Simon was aware that Tryphon would deceive him, both Josephus and 1 Maccabees state that he acceded to both demands so that the people might see that he had done everything possible for his brother. Jonathan was nevertheless treacherously assassinated, and the hostages were not returned. Simon thus became the sole leader of the people.^[4]

As an opponent of Diodotus Tryphon, Simon decided to side with the Seleucid king, Demetrius II, to whom he sent a deputation requesting freedom from taxation for the country. The fact that his request was granted implied recognition of the political independence of Judea.^[4]

He became the first prince of the Hebrew Hasmonean dynasty. He reigned from 142 to 135 BC.

The Hasmonean dynasty was established by a resolution, adopted in 141 BC at a large assembly "of the priests and the people and of the elders of the land, to the effect that Simon should be their leader and high priest forever, until there should arise a faithful prophet".^[7] Recognition of the new dynasty by the Roman Republic was accorded by the Senate about 139 BC, when the delegation representing Simon was in Rome. Simon had made the Jewish people semi-independent of the Seleucid Empire.

In February 135 BC,^[1] Simon and his two sons Mattathias and Judah were assassinated at a banquet at Dok by his son-in-law Ptolemy, the Seleucid governor at Jericho. Simon's third son John Hyrcanus succeeded him as high priest and ruler of Judea but was unable to capture Ptolemy, initially because the latter held John's mother hostage, and subsequently because his army disbanded in observance of the custom at the time of resting every seventh year.

Simon (and its Hebrew form, Simeon) would go on to become the most popular male name for some three centuries afterward in both the Hasmonean Kingdom and Roman Judea. This was both to honor a Jewish hero who had attained independence for the Jewish state, as well as because "Simon" did not sound artificial or strange to Greek ears.^[8][9]