what was his main contribution in that battle he was part of?
His command skills saved the transport ships, which allowed the Romans to pursue a follow up attack at Aspis.
Lucius Manlius Vulso Longus
In the Battle of Cape Ecnomus, his command skills were essential in saving the transport ships, which allowed the Romans to pursue a follow up attack at Aspis. 
in which country did the battle of cape ecnomus take place? Southern Sicily whom was it fought between? Fleets of Carthage and the Roman Republic. which year did it take place? 256 BC can you mention a few warriors from the first group? Hanno and Hamilcar and can you name a few warriors from the second group mentioned earlier? Marcus Atilius Regulus and Lucius Manlius Vulso Longus. with reference to the second person mentioned who belonged to the second group, can you name some of his professions? Roman patrician and Roman consul mention a few duties and responsibilities of that second profession mentioned above. Invested with executive power of the state and headed the government of the Republic. when did he pass away? 216 BC
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Lucius Manlius Vulso Longus [SEP] Analysis of contributions
Throughout the years, Lucius Manlius has generally been accepted as yet another consul who helped in military victories. In the Battle of Cape Ecnomus, his command skills were essential in saving the transport ships, which allowed the Romans to pursue a follow up attack at Aspis. In his second term, he brought the army into an improved and positive state of mind through building a new fleet and recruiting many sailors, even after the losses at Lilybaeum.