Happened to live on upland tract (6)
I believe the answer is:
befell
'happened to' is the definition.
(I've seen this before)
'live on upland tract' is the wordplay.
'live' becomes 'be' (synonyms).
'on' means one lot of letters go next to another.
'upland tract' becomes 'fell' (I've seen this before).
'be'+'fell'='BEFELL'
(Other definitions for befell that I've seen before include "Happened to (someone)" , "Happened, came to pass" .)