Romans didn't use slaves... Cartheginians did. Roman sailors were MARINES, not slaves. Back in the days of that particular Empire, they were called the Second Service. Now, if you admit to being a Cartheginian slave, or perhaps, a Catheginian, period, that would explain why the Irish readers I know like you so much.
Trust me, you aren't going to find anyone my age who knows more about the Romans and the ROMAN empire then me. When it comes to the Romans, the world tends to think of them as the Irish do the English: we over-dramatasize what they did to us. Think of it this way: would YOU let slaves run the motors of a destroyer? You think that if you were the 'captain' of a Roman Galley and you were attacked by Catheginians, who would you rather have at your back, a slave or Marine?
Thought so.
You see, you Marines have a longer reputation for being the Hardest fighters in the world then you thought possible.