Which prophet lamented the death of Josiah?

The prophet who lamented the death of Josiah was Jeremiah. This lamentation is evidenced in the book of Jeremiah, particularly in 2 Chronicles 35:25, which describes how Jeremiah composed a lament for Josiah, mourning his untimely death. Jeremiah recognized Josiah as a king who sought to reinstate true worship and fidelity to God, and his death marked a significant moment in Judah's history, leading to a period of decline and eventual downfall. Jeremiah's sorrow illustrates not only Josiah's personal impact but also the broader implications for the nation of Judah following the loss of such a righteous leader.