LONDON — For more than 600 years, it has been one of the top jobs in Britain. Perks include an apartment next to Big Ben and better pay than the prime minister. And, if you like the sound of your own voice — as the incumbent seems to — there is the added bonus of hearing it broadcast, sometimes around the globe.

With his familiar, braying rebuke — “Order! Order!” — his cheerful put-downs and his constant battle to control a cacophonous and unruly Parliament, the speaker of the House of Commons, John Bercow, has become something of an international celebrity, raising not just his own profile but also that of his successor.

Little wonder, then, that with Mr. Bercow about to step aside after a decade, no fewer than nine lawmakers are vying for the job.

The contest comes at a moment of extraordinary flux for Parliament, with division and paralysis over Britain’s withdrawal from the European Union exposing lawmakers to the wrath of many Britons.