Why were certain senators and government officials killed during the triumvirate?

A triumvirate (Latin: triumvirātus) is a political regime ruled or dominated by three powerful individuals known as triumvirs (Latin: triumviri). The arrangement can be formal or informal. Though the three are notionally equal, this is rarely the case in reality. The term can also be used to describe a state with three different military leaders who all claim to be the sole leader.

In the context of the Soviet Union and Russia, the term troika (Russian for "group of three") is used for "triumvirate". Another synonym is triarchy.

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