The father of Judas Maccabeus, Eleazar Avaran, Simon Thassi, John Gaddi, and Jonathan Apphus, Mattathias was from a rural priestly family from Modi'in.
Like all fit priests, he served in the Temple in Jerusalem.
He was a son of Johanan, grandson of Simeon, the Hasmonean, and great-grandson of Asmon or Hasmonaeus, a Levite of the lineage of Joarib for being the fifth grandson of Idaiah, son of Joarib and grandson of Jachin, in turn a descendant of Phinehas, third High Priest of Israel, according to Mattathias' own words in 1 Maccabees.

After the Seleucid persecutions began, Mattathias returned to Modi'in.
In 167 BCE, when asked by a Seleucid Greek government representative under emperor Antiochus IV Epiphanes to offer sacrifice to the Greek gods, he not only refused to do so, but slew with his own hand the Jew who had stepped forward to do so.
He then killed the government official that required the act.

Let everyone who has zeal for the Law and who stands by the covenant follow me!

— Mattathias, after assassinating the Greek government official,  who was forcing him to sacrifice, Septuagint, 1st Maccabees 2:27.

Upon the edict for his arrest, he took refuge in the wilderness of Judea with his five sons and called upon all Jews to follow him.
Many eventually responded to his call.
Mattathias then disappears from historical record, he probably died c. 166 BCE.
The father of Judas Maccabeus, Eleazar Avaran, Simon Thassi, John Gaddi, and Jonathan Apphus, Mattathias was from a rural priestly family from Modi'in. Like all fit priests, he served in the Temple in Jerusalem. He was a son of Johanan, grandson of Simeon, the Hasmonean, and great-grandson of Asmon or Hasmonaeus, a Levite of the lineage of Joarib for being the fifth grandson of Idaiah, son of Joarib and grandson of Jachin, in turn a descendant of Phinehas, third High Priest of Israel, according to Mattathias' own words in 1 Maccabees.
After the Seleucid persecutions began, Mattathias returned to Modi'in. In 167 BCE, when asked by a Seleucid Greek government representative under emperor Antiochus IV Epiphanes to offer sacrifice to the Greek gods, he not only refused to do so, but slew with his own hand the Jew who had stepped forward to do so. He then killed the government official that required the act.
Let everyone who has zeal for the Law and who stands by the covenant follow me!
— Mattathias, after assassinating the Greek government official,  who was forcing him to sacrifice, Septuagint, 1st Maccabees 2:27.
Upon the edict for his arrest, he took refuge in the wilderness of Judea with his five sons and called upon all Jews to follow him. Many eventually responded to his call. Mattathias then disappears from historical record, he probably died c. 166 BCE.
Mattathias