The consul (in Latin consul) was the highest ranking magistrate of the Roman Republic. The position was annual and collegiate, and two consuls were elected each year among citizens over forty-two years of age. Its task was the direction of the state and, especially, of the army in campaign.
In this way we can see the similarity with the image of the president of the USA of today. We can say that both carried out a similar task, to carry forward the executive power of the nation.