Boris Johnson stunned his nation this week when he announced that he was going to ask Queen Elizabeth II to prorogue Parliament.

The first question that popped up for many was: what does “prorogue” mean? That was followed closely by: why didn’t the Queen slap down the request?

First things first: prorogue means to “discontinue a session of Parliament”. We had to look that up, too.

The second question requires a longer answer. By tradition, what Johnson did on Wednesday amounted to effectively informing the Queen of his plans, not requesting her permission.

Suspending Parliament was clearly a controversial move by Johnson, who is suddenly facing a number of legal and political challenges as a result. The decision to shut down Parliament at this momentous time in the country’s history ­— Britain is set to leave the European Union on October 31 — sparked a furious backlash and angry talk of a “coup” and “constitutional outrage”.

That sounds like something Britain’s 93-year-old monarch would want to steer well clear of. But it is normal for a new prime minister to ask the monarch to prorogue Parliament so that the Government can set out a new legislative agenda. It usually happens every year, resulting in the State Opening of Parliament, which is something akin to the State of the Union, only it involves the Queen and a golden carriage ride and a speech given from a throne. That’s normal here.

What isn’t normal is the length of time that Johnson is suspending Parliament. The five-week break that Johnson asked for is the longest prorogation since 1945.

So why didn’t the monarch simply bat away the request? Or refuse to answer the door when government ministers came knocking at her Scottish estate of Balmoral, where she is on holiday?

Several people on social media said that Johnson was putting the Queen in an “impossible” position. The leaders of the Labour and Liberal Democrat parties said they wrote to the Queen to demand a meeting.

Constitutional experts said that the Queen could — in theory — have said no to the Prime Minister. She could even — in theory — refuse to sign government legislation.

The Queen, by convention, takes advice from her prime minister. The last time a monarch did not accept advice was in the 1830s.

Elizabeth II “acts on the advice of her prime minister”, explained Vernon Bogdanor, author of Beyond Brexit: Towards a British Constitution. “It’s a rule that has served her throughout her reign. It means that any criticism of her decision is directed at the PM and the Government and not the Queen.”

It means that when protesters hit the streets this weekend for nationwide protests, they will be demonstrating against Johnson, not the Queen. It also means that when campaigners take the Government to court — as they are doing in Scotland, England and Northern Ireland — they are arguing about the legality of the advice that Johnson gave to the Queen, not whether the Queen was right to accept it.

But just to be clear: what if Johnson were to ask the Queen something that seemed off-the-charts crazy?

“She could in theory [say no]. If it were so blatant — suppose the prime minister advised her to execute the leader of the opposition,” Bogdanor said. “It’s not in that kind of class. The wise course is always to accept the advice of the prime minister.”

Rodney Brazier, a constitutional expert at the University of Manchester, said in a letter to The Times that the Queen can “warn privately” against advice, “but if the PM persists in his advice the head of state must acquiesce”.

“We should not muddle matters by speaking of the Queen. Boris Johnson alone is responsible for this constitutional fiddle,” he said.

In a recent interview on the BBC, Jacob Rees-Mogg, leader of the House of Commons, who was at Balmoral on Wednesday to deliver the request to suspend Parliament, explained how the process worked.

Rees-Mogg said that a statement was read out in front of the Queen, who simply responded with “approved”.