We were, I think, typical both of a particular class of pre-war Germans and, by contrast, of the post-war country at large. On both sides our family was old, well established and, notwithstanding the wrecked economy, well off.
I don't know how can I receive the bolded part since 'typical' and 'particular' sound opposite to me.
Whatever the link you make between typical and particular, you do not need to be worried that they clash in your sentence. particular simply modifies one of the categories "we were typical of". You can simplify and say:
We were, I think, typical both of A and, by contrast, of B.
where A is
a particular (certain, specific) class of pre-war Germans
We were representative of a particular class, not of any class.
Typical means
having the distinctive qualities of a particular type of person or thing.
You have a certain class of pre-war Germans consisting of a group of people with certain characteristic. The writer is a typical example of those people, as well as the postwar country at large.
