Can someone explain how to make pokemon evolve in Pokemon Conquest

Question

Of course not including the ones that evolve off of stones

Answer 1

This should help you.

Answer 2

Pokémon in the game can grow in strength by increasing their Link with
their Warlord. Depending on how well matched a pair is, the maximum
level of the Link between the two varies, with most Warlords only able
to achieve a 100% or Best Link with a single species of Pokémon. Aside
from growing more powerful, Pokémon may evolve when their Link reaches
a high enough percentage, though there are also Pokémon which evolve
through other conditions such as the use of specific items. Warlords
can also establish links with Pokémon other than the one they started
with, though only one can be used by each Warlord in a given battle at
a time.

http://bulbapedia.bulbagarden.net/wiki/Pokemon_Conquest