An English sentence usually begins with a noun or noun equivalent (subject). But sometimes an adjective is placed first to emphasize the contrast between it and what is stated in the main clause.

Study the following sentence.

Clever as he was, he could not solve the puzzle.

Here as means though and the sentence means: ‘Though he was clever, he could not solve the puzzle.’

More examples are given below:

Strong as he was he could beat his opponent. (= Though he was strong he could not beat his opponent.)
Cold as it was, we went out. = Though it was cold, we went out.
Tired as he was, he went on working. = Though he was tired he went on working.

Inversion of adverb particles

Adverb particles (e.g. up, down, in, out, on, off, away, back etc.) are sometimes inverted for the sake of emphasis.

Off they went on a hunting spree.
Down he fell from his horse.
Up we went to the twenty-first floor.
Out they came from their dirty hiding place.

In the sentences given above the subjects are all personal pronouns and come between the particle and the verb. But if the subject is a noun or any pronoun other than a personal pronoun, it will come after the verb.

Off went the soldiers with the prisoners and booty. (NOT Off the soldiers went with the prisoners …)