Quote:Equites Legionis; These were the cavalry units attached directly to the Legion... Generally this unit would fall under the command of a centurion or optio.
Ah yes - I mentioned these in my second post above - sorry, I was assuming you knew about them already! :wink:
There's no evidence, as far as I know, for centurions commanding them though - there were sixty centurions in the legion, one for each century, so more would be needed if the legion cavalry were a regular centurion's command. But I'm sure a centurion could have been detached to lead them if necessary...
There was a discussion here a while back about whether centurions were mounted - even if they weren't, some would certainly have owned horses, and those directly commissioned from the Equestrian Order would have had their own mounts.
Quote:Do you know anything of the existence of mounted centurions and or optios on scouting, messenger or special duties?
As Jurgen says, the exploratores and speculatores were the usual scouts for the army. There are plenty of cases where centurions were sent off on 'special missions' though. Many of these men were probably Praetorian centurions, who were given official assignments on Imperial business, but in the provinces a legate or governor would have used the legion centurions available in a similar way.
One example: during Trajan's conquest of Parthia, a centurion (probably Praetorian) named Sentius was sent to the fortress of Adenystrae to demand the surrender of its ruler, the Parthian client king Mebarsapes. The king refused, and threw Sentius into the fortress dungeons. Sentius not only escaped from captivity, but led a rebellion of his fellow prisoners, captured the fortress and opened the gates to the advancing Roman army! (Cassius Dio
LXVIII.22)