Those who called it al-Atamah

It is narrated from Sayyiduna Mu'adh bin Jabal (may Allah be pleased with him) that he said: We waited for the Prophet (peace and blessings be upon him) for the Isha prayer. Then he came out to us and said: "Pray this prayer in the darkness (late), for you have been given superiority over all the nations because of it, and no nation before you prayed it."

Sayyiduna Jabir (may Allah be pleased with him) said: The Prophet (peace and blessings be upon him) asked Sayyiduna Abu Bakr: "When do you pray witr?" He replied: "In the early part of the night, after al-Atamah, before I sleep."

Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: When your journey on a given day lasts only until the Atamah prayer, do not shorten the prayer; if it goes beyond that, then shorten it.