Cfxtrjtrk

I have some trouble with the last sentence of this paragraph from Huxley's "The Struggle for Existence in Human Society" (1888) (https://archive.org/details/a588314000huxluoft/page/n223):

The history of civilization–that is, of society–on the other hand, is
the record of the attempts which the human race has made to escape
from this position. The first men who substituted the state of mutual
peace for that of mutual war, whatever the motive which impelled them
to take that step, created society. But, in establishing peace, they
obviously put a limit upon the struggle for existence. Between the
members of that society, at any rate, it was not to be pursued à
outrance. And of all the successive shapes which society has taken,
that most nearly approaches perfection in which the war of individual
against individual is most strictly limited.

Does this translate into more modern/simpler English to the following?

And of all the successive shapes which society has taken,
[the shape] that most nearly approaches perfection [is the one]
in which the war of individual
against individual is most strictly limited.

What troubles me is that the verb be seems to be omitted. Was that acceptable in 19th century English? I am only familiar with this in other languages (say Russian or Latin).
Or am I misunderstanding this sentence?

The primary verb in this sentence is "approaches". To see that, let's start paring off the extraneous bits.

Instead of "And of all the successive shapes which society has taken," let's just say "of all shapes".

Instead of "in which the war of individual against individual is most strictly limited," let's just say "in which war is limited".

The sentence now reads as "Of all shapes, that most nearly approaches perfection in which war is limited." Since the first "that" translates to "that shape out of all shapes", we can rewrite this as "That shape most nearly approaches perfection in which war is limited." Even more simply, we can say "That shape in which war is limited most nearly approaches perfection."

Ergo, "that shape" is the subject of the sentence, and "approaches" is the main verb.