In Roman mythology, the Battle of the Lacus Curtius was the final battle in the war between the Roman Kingdom and the Sabines following Rome's mass abduction of Sabine women to take as brides. It took place during the reign of Romulus, near the Lacus Curtius, future site of the Roman Forum. It concluded when the abducted Sabine women intervened and the two sides sued for peace.

Rome was founded on the Palatine Hill. The settlement flourished and their strength and size came to rival those of their neighbors. The city needed more marriageable women and feared their growth couldn't be sustained if the female population did not increase. Romulus appealed to the other cities in the region:

"Acting on the advice of the senate, Romulus sent envoys amongst the surrounding nations to ask for alliance and the right of intermarriage on behalf of his new community. [...] Nowhere did the envoys meet with a favourable reception. Whilst their proposals were treated with [contempt], there was at the same time a general feeling of alarm at the power so rapidly growing in their midst."

With The Roman people outraged at the response, Romulus announced a festival to be held in the city and invited the citizens of Caenina, Antemnae, Crustumerium, and Sabinia. Once the festivities were underway, Romulus' men abducted the daughters of the Sabines and the other visitors. Afterwards, hostilities broke out between them. Rome defeated three of their enemies, at which point the Sabines declared war.

The two sides spent a year preparing. During this time Rome improved its defenses and were reinforced with Albans soldiers sent by King Numitor and mercenaries under the command of the Romulus' friend and renowned commander Lucumo. After a final effort to resolve the matter peacefully, the Sabine army marched forth.

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