The fruit of a righteous king was prophets and young people who stood for God at a time when not standing for Him would have been comfortable.  Female, male, young, old, with hateful countrymen, or with pagan kings these voices for God carried a common theme and spoke of things in the future.  They stayed true and spoke when it was not easy.

• Huldah is the wife of the wardrobe keeper (Temple garments for the priest). That would make them both Levites.  She was sought out after Josiah was read the Law and he realized just how much his father and grandfather had sinned.  Her word in 2 Chronicles 34: 22 – 28 is good for Josiah, but God has no intention of letting up on Judah.  She tells of the destruction to come, the theme found in all of these prophets of God.
• Jeremiah to me is special. He endured four evil kings, his own family doing him harm, the people rejecting his words from God, seeing the prophesies fulfilled, and finally to die in Egypt where he did not want to be.  As a young man, God gave him a huge task, to test His people (6: 27 – 30).  Parts of Jeremiah are out of order, but I would think that his work during Josiah’s reign is from chapter 1 to 9/10.
• Zephaniah – Chapter 1:1 clearly states the time of his ministry; 3:18 may indicate that he was serving before and during the eighteenth year of Josiah (it refers to “sorrows for the feast”). He may have influenced both Jeremiah and Ezekiel, but the Lord definitely spoke the same words through him that He spoke through Jeremiah and Ezekiel.
• Ezekiel is best known for the visions he received about the new Temple and the new Jerusalem. Chapter 1:1 gives his age and verse two timestamps him starting his ministry in Jehoiachin’s fifth year of exile.  His location is north of the city of Babylon by the Kebar River/Canal.
• Daniel started his role of prophet in Babylon during the reign of Jehoiakim, but he would have been influenced by Josiah and the feast during the thirteen years the Passover was observed. Being a royal he may have also known Jeremiah and had that influence as well. It could be possible that he met Ezekiel, but it is doubtful. Daniel’s locations are south of the one for Ezekiel.  Babylon, Susa, Ulai Canal, and the Tigris River are some of the locations mentioned in the Book of Daniel; it is noteworthy that two of his visions came when he was beside a river.  This custom survived into Paul’s time as seen in Acts 16: 13 when he found Lydia in Philippi.
• Uriah (Jeremiah 26: 20 – 23) Actually, he is mentioned with King Jehoiakim but let’s put the start of his ministry during the time of Josiah. (The reasoning here is time, Jehoiakim was king for eleven years, so he should have been older than that!) He prophesied against Jerusalem and was hunted down and killed by Jehoiakim. This passage does give a look at Jehoiakim and some of his poor conduct.
• There are several false prophets listed in Jeremiah, but like Uriah, we don’t know when they started. They are mentioned in the time period of Zedekiah. Both Jeremiah, Ezekiel, and Zephaniah have sections about false prophets: Jeremiah 23: 33, Ezekiel 13, Zephaniah 3: 4.

The Chronological Bible puts Habakkuk during Josiah’s reign.  That is as good as any place but he could have been with Isaiah and Micah.