Here is how the ranking system works and their roles

Guild Master: 1st in command, this is the creator and is in charge of the guild city and organizing all guild events/ raids/ battlegrounds/ etc.
High Commander: 2nd in command, there is only one of these. This person is the right hand of the guild master. 
Warlord: 3rd in command, there is 1-3 of these and they are in charge of their own division.
Legionnaire: 4th in command, there is 1-3 of these in each division, they are in charge of their own squad. Their job is to train and lead their squad of men into battle.
Blood Officer: 5th in command, there is 1-2 of these in each squad. Their job is to assist their Legionnaire in running the squad.
Templar: 6th in command, this is the highest rank of the basic infantry. Their job is to serve their Legionnaire and Blood Officer.
Blood Guard: 7th in command, this is the middle rank of the basic infantry. Their job is to serve their Legionnaire and Blood Officer.
Guard: 8th in command, this is the lowest rank of the basic infantry. Their job is to serve their Legionnaire and Blood Officer.
Recruit: Person is not officially in the guild yet, but in the application process. Their job is to learn how to serve in the guild.