One's Shakespearean king sent up country (6)
I believe the answer is:
israel
'country' is the definition.
(I know that Israel is a country)
'one's shakespearean king sent up' is the wordplay.
'one's' becomes 'i's' (Roman numeral).
'shakespearean king' becomes 'Lear' (King Lear).
'sent up' is a reversal indicator.
'lear' written backwards gives 'rael'.
'is'+'rael'='ISRAEL'
(Other definitions for israel that I've seen before include "Lear is to be found in this state" , "Middle-Eastern country" , "Eastern Mediterranean country" , "Strange serial country" , "Zion" .)