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This law-making body survived the overthrow of the kings in 509 BCE, the fall of the Roman Republic in the 1st century BCE, the split of the Roman Empire in 395 CE, the fall of the Western Roman Empire in 476 CE, and barbarian rule of Rome in the 5th, 6th, and 7th centuries. In fact, it continued to function in the West Roman Empire until 603 CE. (The upper house of Congress is named for it.)
What is the Senate?