Neriglissar: king of ancient Babylonia, ruled 556.
The Babylonian king Nebuchadnezzar died in 562 and was succeeded in by his son Amel-Marduk, who was almost immediately assassinated and replaced by his brother-in-law Neriglissar. When he died in 556, he was succeeded by his son Labaši-Marduk, who was removed by a coup d'état by a powerful Babylonian nobleman named Belshazzar and several officers.
It is usually assumed that this happened after three months, but the text of the Uruk King List contains a lacuna where one would expect to read an indication for the reign; it cannot be excluded that it said something like "1 year and 3 months". On the other hand, the fact that Ptolemy's Canon does not mention Labaši-Marduk suggests a very short reign. The fact that we don't know any military campaign, is significant as well.
However this may be, the officers put the old scholar Nabonidus on the throne.