In the great tradition of Russian authors as wielders of public authority, a group of prominent writers strolled along a Moscow boulevard Sunday, and thousands of white-ribbon-wearing fans joined in.

At least 10,000 expansively good-natured Muscovites, many arm in arm, others singing favorite old songs, promenaded under the lilacs in full bloom. They were as content as if they were spending a typical Sunday out of town at the dacha, with nothing more important to think about than skewers of lamb and pork for the grill.

But the peaceful stroll was all about rigged elections, political corruption and President Vladi­mir Putin. There were not any signs or banners or speakers’ platforms, so it did not qualify as a demonstration. And that meant no metal detectors to pass through or “cosmonauts” — heavily armed and helmeted police — on hand to bash heads. The only police visible were helping direct traffic around the walkers.

“Look at people’s faces — everyone’s in a good mood,” said Natalya Leleka, a teacher. “It’s like with friends.”

The original idea was to walk from the statue of Alexander Sergeyevich Pushkin, in Pushkin Square, to the statue of Alexander Sergeyevich Griboyedov, another 19th-century poet, at the Chistye Prudy park, a mile or so away. But no one was surprised when the walkers, who turned out in much greater numbers than had been expected, pressed on a bit farther, to the site of what has now been a week-long encampment by the opposition. They call it Occupy Abai, because it centers on yet another statue, one of a 19th-century Kazakh writer known to Russians as Abai Kunanbayev.

Occupy Abai began in reaction to the police crackdown on May 6, on the eve of Putin’s inauguration, when police battled protesters at Bolotnaya Square. Blood flowed, and hundreds were detained. Some in the crowd threw bottles and chunks of asphalt at the police, who responded with vigor.

On this Sunday, only soap bubbles wafted in the air.

Leleka showed off the autographs she had gotten on her white ribbon, the emblem of the opposition here. Boris Akunin, the internationally known mystery writer, had signed, as had Dmitry Muratov, editor of the free-wheeling newspaper Novaya Gazeta; Viktor Shenderovich, a prominent satirist; Olga Romanova, who crusades against false imprisonment; and others.

Two of the opposition’s most charismatic leaders, the blogger Alexei Navalny and the Left Front leader, Sergei Udaltsov, were not there. They are in jail, serving 15-day sentences after being arrested a week ago for wearing white ribbons and for preparing to address the crowd. Others with white ribbons were detained over the next few days, on various streets.

“This is exactly why we are now taking to boulevards and want to show to Muscovites that they can walk where they like, when they like and with ribbons of any color,” Akunin said in an article in the latest issue of Bolshoi Gorod magazine.

As if by mutual agreement, the white-beribboned took to the boulevards Sunday without rancor, and the police stepped back. And so, not for the first time since protests broke out in December, the Moscow narrative swung dramatically away from confrontation and violence.

Valentin Mikhailov, a historian, said the promenaders were taking extreme care not to offer — or react to — any provocation. It’s not like the United States, said Mikhailov, who was a member of the Russian Duma in the early 1990s — one miscalculated act on the part of the opposition could bring the full force of the state down upon it.

As for why the police held back, he said it was clearly a political decision.

“But how to account for political decisions in our country?” he asked. “It’s not possible.”

There’s a tectonic shift happening, said Alexandra Andreyeva, an opposition member of a local district council in Moscow. “We can’t stop it. The authorities can try to influence it. If they try to stop it, it only grows.”

Maybe, she said, the authorities understand that. Or maybe, on Sunday, they just didn’t know how to respond to an event that had no spelled-out political agenda.

And where will this shift take Russia? That, Andreyeva said, no one can know.

Staff writer Kathy Lally contributed to this report.