“Then he blessed them. He was then gathered to his ancestors. He died in the one hundred and forty-sixth year. He was buried in the tomb of his ancestors at Modein. All Israel mourned for him with great lamentation.”
Mattathias blessed his children. Then he died in 166 BCE, 146th year since the beginning of the Greek empire, which was only 1 year after the King Antiochus IV sent out his decree of uniformity in 167 BCE. Mattathias was buried in the tomb of his ancestors, but he had moved from Jerusalem to Modein. How could his ancestors be here and not in Jerusalem? Obviously, not all Israel mourned him. Some might have been mad at him for his attacks on other non-observant Jews.