You need a generic term that applies to any set of interconnected cultures that share a common ethos. That term is civilization. A written body of law is a mark of an advanced civilization, but not a part of its definition.
Main Entry: civ·i·li·za·tion Pronunciation: "si-v&-l&-'zA-sh&n
Function: noun
Date: 1772
1 a :
a relatively high level of cultural and technological development; specifically : the stage of cultural development at which writing and the keeping of written records is attained b : the culture characteristic of a particular time or place
2 : the process of becoming civilized
3 a : refinement of thought, manners, or taste
b : a situation of urban comfort
Main Entry: civ·i·lize
Pronunciation: 'si-v&-"lIz
Function: verb
Inflected Form(s): -lized; -liz·ing
Date: 1601
transitive senses
1 : to cause to develop out of a primitive state; especially : to bring to a technically advanced and rationally ordered stage of cultural development