If George Osborne had wanted a "no change" candidate to squire the Old Lady of Threadneedle Street gently through the next five years, he could have opted for any of several high-flying Brits, including well-respected deputy governor Paul Tucker.
Instead, Bank insiders believe Mark Carney has been handed a mandate for change.
The chancellor is hoping Carney will shake things up on at least three fronts – and on all of them the Canadian faces serious challenges.
First, there is monetary policy-making. The Bank has created an extraordinary £375bn of money through its unprecedented programme of quantitative easing, yet GDP remains more than 2% below its pre-crisis level, making this the weakest recovery from any recession in a century.
There has been some cause for optimism, according to recent data, including the slight fall in unemployment in the latest labour market figures. But Carney stresses the importance of economies reaching "escape velocity", which looks a long way off.
Yet if he hopes to jumpstart the recovery through more monetary stimulus he will have to persuade the monetary policy committee to back him – and six members have repeatedly rejected Sir Mervyn King's calls for a fresh £25bn of quantitative easing in recent months.
As Simon Wells, UK economist at HSBC, puts it: "To start voting for easing they probably need a better reason than 'the new governor wants me to'."
In Canada, Carney pioneered the "forward guidance" approach. As the economy began to pick up in 2009 investors and mortgage borrowers fretted that interest rates would rise; the Bank of Canada responded by publicly promising to keep borrowing costs on hold (provided inflation didn't take off) for a further year.
Osborne has asked the Bank to decide by August whether it would like to adopt a similar approach. But here, too, Carney may face opposition from MPC members, several of whom have expressed scepticism about the idea.
At the Bank of Canada there is a governing council that discusses monetary policy, but no minutes are published, no vote is taken, and what the governor says, goes.
And even if the economy starts recovering strongly at some point during Carney's five-year term he will have to face the fraught question of how to extricate the Bank from its £375bn money-creating spree without sparking a sharp rise in interest rates across financial markets.
Any hint that the Bank is readying itself to sell off some of its huge government bond portfolio, or to push up interest rates, is likely to cause bond investors to take flight, pushing up borrowing costs and potentially putting any recovery at risk.
Fixing the banks
The second fraught area for Carney is Britain's battered financial system. The Bank of England has been handed back the responsibility for supervising the banks, lost in 1997, and the newly-fledged Prudential Regulation Authority will be under his remit.
The authority will have to oversee implementation of the Vickers reforms, which will fundamentally redraw the shape of the UK banking system, imposing a ringfence between banks' high-street operations and their investment arms, which are perceived to be riskier.
Meanwhile, Osborne is charging headlong towards privatisating the bailed-out Lloyds and RBS banks, and the new financial policy committee is involved in a controversial debate over its decision to force banks to raise more capital.
So Carney takes over a bank supervisory regime in flux, at a time when the rules are changing, and the banks are far from recovered from the ravages of the great recession.
Fixing the Bank
The changes to the Bank's remit are also relevant to Carney's third big challenge: fixing the culture of an entity that many feel has become too hierarchical, fusty and out of touch.
Alistair Darling, who had a series of run-ins with Carney's predecessor, King, during the financial crisis, referred to the latter as the "sun king", with untrammelled power in Threadneedle Street.
The Bank has already changed radically since the downturn hit. But Carney will be expected to bring the institution into the 21st century.
A public survey, published in the Bank of England quarterly bulletin, shows that while public confidence in the institution has grown, the sharp drop that occurred with the onset of the crisis has yet to be reversed.
Fewer than half of households – 35% to 40% – said, in this survey, that they were "fairly or very satisfied" with the way the Bank was doing its job, and 20% to 30% were "fairly or very dissatisfied". The new governor will be hoping to improve those ratings.
Even for someone with Carney's impressive reputation, these appear a formidable set of challenges. But as Craig Wright, the Royal Bank of Canada's chief economist, puts it: "Firefighters go where the fires are."
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