Final answer:
Sequoyah is the Cherokee leader who developed a written syllabary of the Cherokee language.
Step-by-step explanation:
The Cherokee leader who developed a written syllabary of the Cherokee language was Sequoyah. He created a system of writing for the Cherokee language in the early 19th century. This syllabary consisted of characters representing syllables rather than individual sounds, making it easier for Cherokee people to read and write.
Learn more about Cherokee language and writing system