How do translators decide what to use for the title of books of the Bible?

I've noticed occasionally, people use slightly different names for the books of of the Bible (especially in older literature). For example, sometimes Revelation is called Apocalypse. In the Orthodox Study Bible, the books of Samuel-Kings are titled 1-4 Kingdoms, and 1-2 Chronicles are called 1-2 Paralipomenon. The Wycliffe bible has "Deeds of the Apostles" instead of "Acts of the Apostles". Based on this neat article on Wikipedia , I'm guessing that part of this goes back to the differences between titles in KJV and Douay-Rheimes. In other language versions of the Bible, I've also noticed some differing names for the books of the bible. For instance, in Chinese Bibles, the book of Exodus is titled "出埃及" (literally, "exiting Egypt"). That's a pretty good title; it's short and descriptive. This all got me thinking: **What considerations do translators make when deciding what to title Biblical books?** In English, we largely now follow the precedents set by the King James, but that doesn't explain the KJV's translators reasoning originally. It seems that the books that are named after people/places (the Gospels, the Epistles, and the Prophets) are pretty uniform across languages, but other books less so. For the other books, I don't see much of a pattern regarding the usage of **transliterations or common vs. uncommon vs. archaic words** for these translations. ------ Here's few other variants in meaning I see between the Bibles of the three languages that I speak (with my non-expert translations to English; I am a native speaker of English so please correct me if I've misunderstood anything in Chinese or Mongolian). I've also noted when some words are uncommon or archaic (neither of the Asian languages are using transliterations other than for the books named after people/places): | English | Chinese | Mongolian | translation of Chinese name | translation of Mongolian name | | ------- | --------- | --------- | --------------------------- | --------------------- | | Genesis | 创世记 | Эхлэл | "Record of the creation of the world" | "Beginning" | | Exodus | 出埃及记 | Гэтлэл | "Record of exiting Egypt" | "Conquest" - this is not a common word in Mongolian (it's not in the most popular English-Mongolian dictionary at all); It is the noun form of the verb "гэтлэх" meaning to conquer/overcome (also not the most common word for this concept). | | Deuteronomy | 申命记 | Дэд хууль | "Record of the repeated commands" - using an archaic meaning of the character 申 as "repeat", which in modern Chinese means "stretch", "announce", or "request". | "Secondary law" | | Psalms | 诗篇 | дуулал | "poems" | "anthems" (it's a rare word for "song", otherwise mainly used to refer to the national anthem) | | Ecclesiastes | 传道书 | номлогчийн үгс | "Book of preaching" | "words of the preacher" | | Song of Songs | 雅歌 | Соломоны дуун | "Elegant song" | "Solomon's song" | | Acts | 使徒行书 | Үйлс | "Book of the Apostles' Actions" - same as the full English title. I've included it because it is abbreviated to "disciples" (徒) instead of "acts" like in English | "acts" | My Mongolian Bible (Mongolian Bible Society 2019 version) includes brief introductions to each book, but they don't explain the choice of words for titles (especially, whether to use a common, a rare word, or an archaic word). Interestingly, for the book of Exodus it does explain the origin of the *Greek* title, but not why the specific Mongolian word 'Гэтлэл' was chosen. Please note I'm not asking *specifically* about these three languages, but rather a more general question about the kinds of logic that translators use to make these decisions. Some examples from other languages that I don't speak would still be a good answer. ----- P.S. For more documentation, and just for fun, here's some interesting examples other users have pointed out: * In Finnish bibles, the five books of the Pentateuch are simply titled "First book of Moses", "Second book of Moses", etc. (suggested by user JiK) * Song of Solomon in the Russian Synodal Version has the title "Song of Songs of Solomon" (suggested by user Seggan)