English is far from the only language spoken in Britain.

Significant time and resources have been put toward preserving indigenous minority languages across Britain, including Welsh, Gaelic, Scots and Irish. And, of course, many other languages are spoken — among them, Polish, Punjabi, Arabic and French.

It’s understandable how Boris Johnson, a front-runner to replace British Prime Minister Theresa May at 10 Downing Street, ruffled some feathers on Friday when he said, “There are too often parts of our country … where English is not spoken by some people as their first language.”

“And that needs to be changed,” he said.

The most important priority for immigrants should be “to be and to feel British,” he said, “and to learn English.”

The comments sparked outrage across Britain, where they were seen as echoing populist talking points targeting immigrants and disrespecting centuries-old languages indigenous to the region.

Scottish lawmaker Angus MacNeil tweeted, “Boris is just moronic & clueless.”

“Same arrogance of centuries past that did down native Celtic languages for the Germanic import,” he wrote, referring to the English language’s West Germanic roots. “Multilingualism please Boris and drop the cultural imperialism.”

Even Johnson’s sister Rachel derided the comments, tweeting that their family “spoke Ancient Greek at home.”

“I genuinely don’t know what he’s on about,” she wrote.

Since British voters opted to leave the European Union, representatives of minority-language groups have expressed concerns that Brexit could marginalize certain groups that have relied on European funding for the protection and promotion of their indigenous languages.

In recent years, activists have urged governments to invest in preserving indigenous languages. In Wales, for example, the government has pledged to have 1 million people speaking Welsh by 2050. This week, the British government announced a fund intended to preserve the Cornish language.

The United Kingdom’s 2011 census found that in England and Wales, more than 90 percent of people spoke English or Welsh as their first language. Around 7.7 percent of the population reported that they spoke another main language, although the proportion in London was much higher, at about 22 percent. Polish was the most widely spoken other language, followed by Punjabi and Urdu.

Only 1.3 percent of the population said they could not speak English well, and just 0.3 percent said they could not speak it at all.

Other politicians have made comments similar to Johnson’s. In 2014, Nigel Farage, now the Brexit Party leader, said parts of Britain felt like a “foreign land.”

He claimed that, “in many parts of England, you don’t hear English spoken anymore.”

“This is not the kind of community we want to leave to our children and grandchildren,” he said, adding that he felt “slightly awkward” on a train where he heard people speaking other languages.

Similar debates have unfolded in the United States. On the campaign trail in 2015, Donald Trump criticized fellow Republican presidential candidate Jeb Bush, the former governor of Florida, for speaking Spanish. “He should really set an example by speaking English in the United States,” Trump said.

When asked about that comment in a Republican debate, Trump said he meant it “a little halfheartedly,” but then he doubled down on the point.

“We have a country where to assimilate, you have to speak English,” he said. “We have to have assimilation to have a country. We have to have assimilation.”

“This is a country where we speak English, not Spanish,” he repeated, more loudly.

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