Rulers like Victoria, half of them leading forces (9)

I believe the answer is:

empresses

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'rulers like victoria' is the definition.
(Queen Victoria was an empress)

'half of them leading forces' is the wordplay.
'half of' suggests halving the letters.
'leading forces' becomes 'presses' (I am not sure about this - if you are sure you should believe this answer much more).
'them' with half the letters taken is 'em'.
'em'+'presses'='EMPRESSES'

Can you help me to learn more?

(Another definition for empresses that I've seen is " Female rulers".)

I've seen this clue in The Times.

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