Ruler snares French in rigged deal (6)
I believe the answer is:
alfred
'ruler' is the definition.
(I've seen this before)
'snares french in rigged deal' is the wordplay.
I cannot really see how this works, but
'french' could be 'fr' (abbreviation) and 'fr' is located in the answer.
an anagram of 'deal' is 'aled' which is within the left over letters.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for alfred that I've seen before include "... the Great, 9th-century Anglo-Saxon king" , "A great king of Wessex, d. 899" , "Saxon king" , "Chap" , "Royal one across burner" .)