Answer 1
Zephaniah was put death by King Nebuchadnezzar of Babylon.
Answer 2
As a researcher and contributor, I'm unable to find any biblical record of the death of Zephaniah. It appears the answer is, "Unknown."
Answer 3
Jeremiah 52:24-27 explains how King Nebuchadnezzar killed Zephaniah
Additional Comments:
Jewish names are like many others where there are usually more than one person with the same given name - even in a similar line of work. This seems to be the case here with Answer 3 above. The priest name Zephaniah in the Book of Jeremiah 52:24-27 appears to be the same man as noted in Jeremiah 29:25, at least they share the same given name. This figure does not appear to be the Prophet Zephaniah.
The Prophet Zephaniah who wrote a book in the Old Testament, was a contemporary of Jeremiah. He lists his genealogy back four generations to Hezekiah (probably Judah's King then) as follows: son of Cushi, son of Gedaliah, son of Amariah, son of Hezekiah in the days of Josiah, King of Judah - circa 627 BC.
On the other hand, the priest Zephaniah mentioned in Jeremiah 29 and 52 says he is the son of Maaseiah. So, it is obviously a different Zephaniah than the 'minor prophet' Zephaniah of whom the Scripture does not note his date/way of death.
The author of the Book of Zephaniah is the prophet Zephaniah. The author of the Book of Zechariah is the prophet Zechariah.
There is no specific information on Zephaniah's occupation before he became a prophet. He is mainly known for being a prophet who delivered messages from God to the people of Judah.
Zephaniah
Zephaniah.
Zephaniah preached his message through his writings. He would write about what God had said to him (speaking because he was a prophet).
Zephaniah Swift died in 1823.
Zephaniah Kingsley died in 1843.
Most probably Zephaniah lived around Jerusalem.
John Zephaniah Holwell died in 1798.
Dewi Zephaniah Phillips died on 2006-07-25.
Zephaniah Swift Moore died on 1823-06-29.
If you're talking about the poet, Benjamin Zephaniah is not dead and is living in East London