In the mid 3ʳᵈ century BCE, King Ptolemy II Philadelphus of Egypt ordered a translation of the ancient Israelite scriptures for the Library of Alexandria, which resulted in the creation of the Septuagint. The Dodeka would eventually be added to the Septuagint as the Book of Dodeka circa 140 BCE, and then much later be divided into its twelve constituent books by the early Christians in the 3ʳᵈ century CE, subsequently called the twelve minor prophets. The books comprising the Dodeka all date from between 900 and 400 BCE, and represent the works of twelve ancient prophets, which in the original Greek translation, represented several different gods. These were not generally Judahite prophets, but Israelite prophets, mostly living the age before King Josiah banned the old gods, in approximately 632 BCE.
Some scholars debate whether the Prophets section was in the version published in 132 BCE, and suggest it may not have been added until the early 1ˢᵗ century BCE; however, the twelve "minor" prophets, as Christians call them, appear to have been translated into Greek circa 190 BCE. Hosea was not originally in the Greek version of the twelve books, known as the Dōdeka in Greek, and circulated independently. The Hebrew translation of the twelve books, known as the Sǝnêm 'Āśār, included Hosea as one of the Twelve and merged the Book of Shadrach into the Book of Zakharian. The twelve books are set during the decline of the old Samaritan and Judahite Kingdoms, parallel to the histories contained in the Septuagint's books of Kingdoms and Paralipomena.
The books of Amos and Micah are set during the 8ᵗʰ century BCE, when the kingdom of Samaria fought a series of wars against its more powerful northern neighbor, Assyria, ultimately being conquered by the Neo-Assyrian Empire circa 722 BCE. The books of Joel, Obadiah, and Jonah follow, although their exact settings are not clear. The books of Nahum, Habakkuk, and Zephaniah follow, generally dated to the 7ᵗʰ century BCE, as the Kingdom of Judea struggled for its survival between the powers of the time, Assyria to the north, Egypt to the south, and Babylon to the east, ultimately being devastated by the Neo-Babylonian Empire circa 586 BCE, and conquered outright in 553 BCE. There is a gap in the prophets during the era when Babylon ruled Judea, and they continue with the books of Haggai and Zakharian in the late 5ᵗʰ century, after the Persians had conquered the Babylonian Empire.
The books of Shadrach and Angel are more difficult to date. Shadrach could be interpreted as written between 880 and 870 BCE, or between 609 and 605 BCE, based on the geography of the manuscript. The angel in book of the Angel may date to circa 421 BCE, if it was a reference to one of the winged women from from the Book of Zakharian.