Japan had no writing system
When Japan first encountered Chinese writing in the 4th–5th centuries CE, it had a fully developed spoken language but no written form. The solution was pragmatic: adopt Chinese characters (kanji) and adapt them to write Japanese. The challenge was that Chinese and Japanese are completely unrelated languages with different grammar, different word order, and very different sound systems.
Man'yōgana: the bridge script
The first solution was 万葉仮名 (man'yōgana): using kanji purely for their sound rather than their meaning, to spell out Japanese words phonetically. The same character might represent a sound in one context and a meaning in another, creating a complex system that required extensive knowledge to read. The 万葉集 (Man'yōshū, the oldest anthology of Japanese poetry, 8th century) is named for this script.
Some of the most elegant Japanese poetry was written in man'yōgana — a script so complex that much of the anthology could not be fully read for centuries. Modern scholars continue to debate the reading of some passages. The complexity of the script was itself a sign of literary sophistication in the Nara period.
Hiragana: the women's script that changed everything
In the Heian period (794–1185), simplified cursive forms of kanji — used primarily by women at court, who were not expected to study the formal Chinese learning of men — evolved into hiragana. The Lady Murasaki Shikibu wrote 源氏物語 (The Tale of Genji) in hiragana around 1000 CE. This became one of the world's first novels — proof that a "simplified" script could carry the greatest literature.
Katakana: the monks' shorthand
Katakana developed separately, in Buddhist temples and academies, where monks needed quick shorthand to annotate Chinese texts. They took single components from kanji and used them to represent syllable sounds: ア from 阿, イ from 伊, ウ from 宇. Katakana's angular, abbreviated forms reflect this documentary, clerical origin — distinct from the flowing curves of hiragana that emerged from court calligraphy.