I'm very curious. If King Sejong invented Korean alphabet, who created the Japanese alphabet?

* Japanese is a relative of the Altaic language family. Other languages in this group include Mongolian, and Turkish. Evidence for this theory lies in the fact that like Turkish and Korean, Japanese is an agglutinative language. Japanese also has two (phonologically distinctive) tones, similar to Serbian/Croatian and Swedish. This tonal system is often referred to as a pitch accent in linguistics. Additionally, there are a suggestive number of apparently regular correspondences in basic vocabulary, such as ishi "stone" to Turkic daş, yottsu "four" to Turkic dört.
* Japanese is a relative of other Asian languages. This theory maintains that Japanese split from - or had large influences from - other East Asian languages such as Korean (and possibly the Sino-Tibetan languages). Phonological and lexical similarities to Malayo-Polynesian languages have been noted.
* Japanese is related to southern Asian languages. Some researchers have suggested a possible relationship between Japanese and Tamil, a member of the Dravidian language family spoken in southern India.
* Japanese is a kind of creole, with an Altaic grammatical substructure, and core Austronesian vocabulary.
* Japanese is a language isolate, unrelated to any other known language except other Japonic languages (notably Okinawan).

Serbo-Croatian is a slavic language. Swedish is a Germanic language. Anyways, the "Altaic myth" is a remenant from the old Soviet-era linguists who couldn't do any better than to classify them. Structurally, Japanese and Korean are somewhat related, however. Furthermore, in terms of phonology, Japanese is quite similar to Uralic languages, though morphology has not been attested to. Thus, some have speculated: Ural-Altaic(?) >> Uralic >> Samoyedic >> Koreanic/Japonic. Keep in mind, of course, that Korea/Japan are racially Samoyedic-related to some degree.

The Altaic is a putative language family which would include 60 languages spoken by about 250 million people, mostly in and around central Asia. The relationships among these languages remain a matter of debate among historical linguists, and the existence of Altaic as a family is rejected by many. Its proponents consider it to include the Turkic languages, the Mongolian languages and the Tungusic languages (or Manchu-Tungus). The Japonic languages and Korean are often also included, and Ainu has been suggested by some, into an "Altaic superfamily." However, the evidence for this is not solid enough to do so.


Also not so accurate. Sino-Tibetan languages are synthetic (at times polysynthetic). The only resemblance is a large number of loan words from Tang (Middle) Chinese.


At present, most evidence supports this.

And for all your errors, you failed to answer the question. Hiragana and katakana developed from simplifications over time of Chinese characters. See below:

Hiragana syllables developed from Chinese characters, as shown below. Hiragana were originally called onnade or 'women's hand' as were used mainly by women - men wrote in kanji and katakana. By the 10th century, hiragana were used by everybody. The word hiragana means "oridinary syllabic script".

The katakana syllabary was derived from abbreviated Chinese characters used by Buddhist monks to indicate the correct pronunciations of Chinese texts in the 9th century. At first there were many different symbols to represent one syllable of spoken Japanese, but over the years the system was streamlined. By the 14th century, there was a more or less one-to-one correspondence between spoken and written syllables.

Take it up with wikipedia. Not me

Murasaki got lazy with writing chinese and took bits of it to make a new alphabet.

Kana was invented by Kūkai, a Buddhist priest. Yes, kana developed from simplifications of Chinese characters but Siddham, a north Indian script used primarily to write Sanskrit, was also influential in the development of kana