Ense petit placidam sub libertate quietem

Ense petit placidam sub libertate quietem is a Latin passage and the official motto of the U.S. Commonwealth of Massachusetts and the University of Massachusetts Amherst.

The literal translation, however, is "she seeks with the sword peaceful repose under liberty."

The "she" in question refers to the word manus from the full phrase manus haec inimica tyrannis ense petit placidam sub libertate quietem, which means "this hand, an enemy to tyrants, seeks with the sword peaceful repose under liberty."

It was written c. 1660 by the English soldier-statesman Algernon Sidney, who was an opponent of Charles II and who was later executed for treason.

On December 13, 1780, the legislature approved its application to the current Great Seal of Massachusetts.

Ense petit placidam sub libertate quietem used on the coat of arms of Massachusetts