Eleazar ha-Kalir

Yose ben Yose, Yannai, and Eleazar ha-Kalir, or ben Kalir—lived in that order, but when or where in Palestine any of them lived is not known. The accepted datings are 3rd century and 5th–6th century ad. Many piyyuṭim are still used in the synagogue.

…Yose, Yannai, and his pupil Eleazar Kalir, none of whose dates can be fixed with certainty.