Answer:
There are many.
1. king/queen
2. duke/duchess
3. masquerade/marquess
4. count/countess
5. viscount/viscountess
Step-by-step explanation:
sorry for bad spelling, ps some info may be wrong i have to check again but a knight is definetly higher than a commoner. They can also be higher than the above ranks if one of the nobles like a count decide to become a soldier. :)