What caused the early Romans to move away from a monarchy and start a republic

During the period of kings (monarchy) Roman citizens weren't satisfied with the way how they were governed. Kings ruled without restrictions, quite often were tyrants, and that is why the last one Tarquin The Proud was overthrown. A period of Republic that was established meant that people had more influence in the decision-making process through certain institutions, such as Senate and Tribunate.

Explanation:

Period of Kings lasted from 753 BC, when the city of Rome was built until 509 BC when the last king was overthrown. Rome in that period didn't spread much, and when the Republic was established things have changed a lot. Citizens of Rome had more opportunity to govern themselves, through certain institutions. Even the gap between plebeians and patricians has changed with certain laws that were brought.

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