Hi Rank, can you give a reference for that Wiki article on the battle please? Couldn't find it, and although it might not have anything to do with the song it would be interesting to see.

I suppose "Leghorn Roads" would be the approach to Genoa. Don't know anything about Adm. Kempthorne, except that he is mentioned by Samuel Pepys.

There are a couple of similar songs I've heard, such as "Capt. Mansfield's Fight", which has a ccompletely different tune.