As mentioned, Birthright is both a low-leveled setting, as well as a low-magical setting.

What this means for levels, is that a 4th level character in this setting is rather high leveled. He is an expert of is field.

A common person is an expert level 1, most people in the armies are level 1 warriors.

A sargeant or a Knight would often be a level 1 Fighter.

A grissled and experienced old knight, would probably a Fighter 4.

Usually only blooded people, or experienced adventurers, can hope and expect to go beyond.

A 4th level si a Master at his proffession.
A 5th level is a Grandmaster at his proffession.

So all of you running around with higher levels then that are looked with awe by the general peon on the street if they have heard about some of the things you can do. Thus you can rightly call yourself a "high level" character.