Looking back with honour to accept the origins of this royal office (10)
I believe the answer is:
retrospect
'looking back' is the definition.
(I've seen this before)
'honour to accept the origins of this royal office' is the wordplay.
'honour' becomes 'respect' (respect is a kind of honour**).
'to accept' is an insertion indicator.
'the origins of' indicates taking the first letters.
The initial letters of 'this royal office' is 'tro'.
'respect' placed around 'tro' is 'RETROSPECT'.
'with' is the link.
(Other definitions for retrospect that I've seen before include "A backward view" , "Hindsight" , "Survey of past events" , "Look(ing) back" , "Look at history" .)