Cryptic crossword clue
German traders once allied in northern constituency, one almost certain to be held by old Tory leader 9,6

The most common and most likely answer to this crossword clue is the 9 plus 6 letter word HANSEATIC LEAGUE

I've seen this crossword clue in Independent
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Buddy explains!

The straight part
We know that "German traders, once allied" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case german traders, once allied = hanseatic league.
The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.
This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.

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