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to install (a king, emperor, etc.)
to appoint (to a post); to promote
to assign (to study under)
幼い皇太子を帝位に即けた。
They installed the young crown prince on the imperial throne.
大臣たちが新しい王を即けることを決めた。
The ministers decided to install a new king.
長い内乱の末にようやく正統な後継者を即けた。
After a long civil war, they finally installed the legitimate successor.