Indian quickly protecting leader of Hindus (6)
I believe the answer is:
apache
'indian' is the definition.
(Apache is an example)
'quickly protecting leader of hindus' is the wordplay.
'quickly' becomes 'apace' ('apace' can be a synonym of 'quickly').
'protecting' means one lot of letters goes inside another.
'leader of' indicates taking the first letters.
The initial letter of 'hindus' is 'h'.
'apace' placed around 'h' is 'APACHE'.
(Other definitions for apache that I've seen before include "North American native tribe" , "member of tribe" , "Parisian gangster" , "A North American Indian or old Parisian thief" , "North American Indian tribe - Paris ruffian" .)