PARIS — Seated on apple-green plastic chairs in a windowless, low-ceilinged room in a back street annex of the Prefecture de Paris, some 70 new French citizens waited excitedly to receive their precious nationality papers.

To some, it was the end of a harrowing journey from persecution, war, poverty or statelessness. To others, the chance to live permanently with a loved one or secure the right to work in Europe.

For me, born and raised in Britain, it was an emotional and intellectual fusion with the country I had studied as a historian, where I had been a teacher and served three postings as a foreign correspondent, and where I now live as a columnist and think tank researcher.

I choked back tears as we sang “La Marseillaise” at the climax of a ceremony that featured a lecture on the values of Liberty, Equality and Fraternity, with heavy emphasis on secularism. We were shown a video showcasing the history and architectural treasures of France, dwelling on the French Revolution and the Declaration of the Rights of Man and the Citizen. Images of Rafale fighters, Mistral warships, TGV trains and Airbus planes raced by and, yes, there were scenes of strikes and protest marches (though not of burning barricades or tear gas). I thought I spotted King Louis XVI being guillotined in the Revolution section, but it flashed past so quickly I can’t be sure.

The representative of the Paris prefect (the police chief and state administrator) highlighted to our diverse group from 27 countries the huge contribution of foreign-born French citizens to the nation’s literature, arts, science and economy. He cited poet Guillaume Apollinaire and novelist Milan Kundera as well as composer Jacques Offenbach and scientist Marie Skłodowska Curie.

“You have made the beautiful and noble choice of becoming French. Welcome to our national community,” Christian Hausmann, the head of the immigration and naturalization bureau, said. “You can be proud to be French. France is proud to welcome you.”

It seemed such a generous embrace that I was not minded to quibble when he spoke of “the human rights which our nation gave to the rest of the world.” Historians might have put in a word for England’s Magna Carta, habeas corpus and the Virginia Declaration of the Rights of Man, but this was no time for a paternity suit.

Many friends have assumed that I am simply a refugee from Brexit, acquiring a flag of convenience. One wrote on Facebook, “Pray God this not be a rat fleeing a sinking ship.” Another said I was “saved from the flood waters” in the nick of time, two months before the U.K. is due to leave the European Union.

I know dozens of Brits who are seeking or have obtained Belgian, Irish, French, German or Portuguese passports to protect their right to work, live, travel freely and receive public health care in the EU from the still incalculable uncertainties of Brexit.

Prime Minister Theresa May’s stigmatizing of Britons who considered themselves citizens of the world as “citizens of nowhere” was just the final straw. I decided to become a citizen of somewhere.

So let’s get one thing straight: I decided many years ago that when I finally stopped traveling the world as a nomadic journalist with Reuters and settled in France with my French wife, near my French children and French grandchildren, I would apply for citizenship.

I pay my taxes here, and will gain no new benefits that I didn’t have as a spouse of a French national.

It’s about much more than Brexit. I’ve always wanted to engage fully in the civic life of the community where I had chosen to live.

For sure, being prevented from voting in the 2016 referendum under British law because I had lived abroad for 15 years (in the European Union) hastened my application. Prime Minister Theresa May’s stigmatizing of Britons who considered themselves citizens of the world as “citizens of nowhere” was just the final straw. I decided to become a citizen of somewhere.

The only time I have previously voted in France was in the 1994 European Parliament election. It was the first time European citizens resident in another member country had the right to cast ballots under the 1992 Treaty of Maastricht.

I took my 6-year-old daughter along to the polling station to see European democracy in action. But I had forgotten to explain to her it was a secret ballot. When I emerged from the voting booth to slip my envelope in the perspex box, she shouted: “Mon papa a voté Rocard!” (Daddy voted for Rocard). That's Michel Rocard, a former prime minister, who topped the center-left Socialist ticket which, for the first time, had equal numbers of men and women, earning it the nickname “shabadabada” after the theme tune from Claude Lelouch’s film “Un homme et une femme.”

There was a moment of consternation, then laughter. The scrutineers decided my vote was valid.

That experience was a miniature of the dilemmas I now face. After four decades as a professional foreign observer of French society and politics, I am suddenly an actor, in my modest way.

Will I support the gilets jaunes occupying roundabouts and marching every Saturday in high-visibility jackets to demand cheaper fuel, pay rises, tax cuts except for the wealthy and direct plebiscitary democracy? Will I lean towards the foulards rouges (Red Scarves) who support a peaceful national dialogue and condemn the sometimes violent protesters?

What is my position on a bill enabling a police chief to ban individuals classified as dangerous from joining a demonstration, even without a court order or criminal conviction? How should France square its secular principles and the neutrality of the state with the need to live together in harmony with a large Muslim minority, many of whom feel victims of discrimination and racism? It’s my problem too now.

As a citizen, I should have views about such matters, as well as on France’s nuclear deterrent or whether it should intervene militarily in Libya, Syria or Mali. Suddenly, it’s my country too.

I’m still a Brit by birth, education and passport.

And then there is Brexit. Should France stick to its tough line of refusing any renegotiation of the Withdrawal Agreement that the 27 other EU countries reached with Britain last November? Or should it encourage more flexibility to preserve cross-Channel trade and traffic from chaos if the U.K. leaves without a ratified deal on March 29?

Once the wine-stained celebrations of my new citizenship subside, I’ve got some serious thinking to do. I’m still a Brit by birth, education and passport. God only knows who I’m going to cheer for when my mate Jean-Pierre and I settle down with a bottle of Calvados to watch the France-England rugby match.

Meantime, I’m proud and grateful to have become a citizen of a great European democracy, and to be remaining a citizen of the European Union.

Not everything here is rosy, but Vive La République! Vive La France!

Paul Taylor, contributing editor at POLITICO, writes the Europe At Large column.