Valaam, Russia - Varvara Sergeeva's great-grandfather was among the tens of thousands of clerics, monks, nuns and believers executed by Communist iconoclasts in 1937. Pavel Orleansky had served as a deacon in the revered Orthodox Christian monastery on Valaam, the lake island just south of Finland.

Sergeeva learned about his fate from declassified KGB archives in 1988, when during the Perestroika reforms the USSR celebrated a millennium of Christianity in Russia.

Soon after graduating from high school, Sergeeva decided to get baptised and leave her native St Petersburg for Valaam to help revive the monastery.

"I felt absolute happiness. What was happening was unreal," says the stately, fair-haired 44-year-old at a cafe in St Petersburg. "It's a wonderful place, very pure, very vivid."

But in the past decade, Sergeeva and her son have faced a forced eviction from their Valaam apartment, an arson, confiscation of property, a string of lost trials and debilitating health problems, all as a result of the resurgence of the monastery and the Orthodox faith in Russia, and the Kremlin-backed restitution of religious property.

Embracing Orthodoxy after Communism

After the 1917 Bolshevik revolution, Communists uprooted Russia's Christian, Muslim, Jewish and Buddhist communities. They destroyed thousands of religious buildings and turned many more - along with their land - into museums, schools, theatres, police stations, prisons, collective farms and parks.

But the Russian Orthodox Church, the czarist empire's dominant creed, did not own most of the properties. For almost three centuries, the Church has functioned as a government institution whose clerics served in churches and chapels built and maintained by nobles, merchants, other government bodies, the military, and civilian communities.

In the post-Soviet 1990s, many Russians embraced Orthodoxy believing the Patriarchate of Moscow would help Russia exorcise the Communist doctrine.

"The Church was very open and most people had unconscious hopes that the Church would help build a democratic, free Russia," says Roman Lunkin of the Russian Academy of Science's Institute of Europe.

The Kremlin started a nationwide effort to restitute religious properties, often prime real estate in city centres or recreational spots. But the Patriarchate has been selective. Instead of restoring thousands of decrepit churches, it has focused on well-known sites which could turn a profit and whose maintenance the Kremlin pays for, Lunkin says.

"They choose symbolic, significant sites and ask the government to keep financing them," he says.

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The influential Patriarchate

The Patriarchate, however, is far from destitute.

President Boris Yeltsin let it run tax-exempt businesses that sold alcohol, tobacco and oil, and now those businesses include publishing houses, farms, construction companies, shopping malls and hotels.

The Patriarchate never releases its financial records, and its annual profits roughly amount to $1-1.2bn, says Nikolay Mitrokhin, Russia's leading expert on the church economy. It also gets sizable donations from the state, major businesses and worshippers.

Patriarch Kirill of Moscow was spotted wearing a $30,000 wristwatch in 2012. The septuagenarian travels by personal jet, a custom-made, bulletproof limousine and a luxury yacht, which has a private dock on Valaam.

By 2010, when a federal law made restitution easier, the Kremlin saw Orthodoxy as providing an important ideological function.

"The Communist ideology ceased to exist and a real ideological vacuum emerged. And it could not be filled by anything other than religion," President Vladimir Putin said in June.

But the way the Patriarchate propagates its viewpoint is increasingly repressive.

Its clerics consecrate nuclear missiles, calling them "Russia's guardian angels". It blesses the Kremlin's aggressive anti-Western nationalism by extolling Russia as an heir to the Byzantine empire which opposed the Catholic West for centuries. Patriarch Kirill's conception of the "Russian world", or Moscow's duty to "defend" millions of ethnic Russians in ex-Soviet republics, back the Kremlin's renewed assertiveness.

"These ideas justified the invasion in Ukraine - ideologically," Mitrokhin says, referring to a massive campaign in Kremlin-controlled media that claimed Ukrainian authorities were conducting a "genocide" of ethnic Russians.

The Patriarchate condemns same-sex marriages, abortions, sex education and HIV-prevention programmes, and seeks to introduce compulsory religion classes in schools. It welcomes official pressure on other religious groups - including splinter Orthodox movements and Protestants - such as a court ban of Jehovah's Witnesses in July for their "extremist" teachings. Patriarchate-affiliated groups assault critics, attack gay clubs and enlist neo-Nazis and aggressive football fans.

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Arson and evictions

When Sergeeva settled on the forested island half the size of Manhattan in the late 1980s, the disbanded monastery's buildings belonged to a museum. She found an apartment in the Winter Hotel, a residence of museum employees who restored medieval icons and frescoes. She and hundreds of secular island residents unanimously approved the return of monks to Valaam in 1989.

Sergeeva made a living by sewing clothes for monks and souvenir bags for tourists. She contributed money towards the renovation of the chapel her great-grandfather had served in and raised her son Dmitri as an observant Christian.

But after the monastery restituted its buildings in the early 1990s, it started forcing out all secular islanders who did not work for it, offering them apartments in mainland towns addled by unemployment. Sergeeva refuses to accept an apartment in a former slaughterhouse with new cladding but no heating. Medical experts found that toxic fungi and mould covered its concrete walls.

After years of desperate resistance to the eviction and several lost trials, she developed a chronic heart condition and her son was diagnosed with bone cancer. Dmitri, who is in remission after lengthy chemotherapy, awaits surgery, she says.

"Bishop Pankraty [Valaam's head], is forcing us to commit suicide, given our health status," says Sergeeva, who now lives with her son and parents in St Petersburg.

In 2016, a fire damaged the Winter Hotel and some 60 residents left, especially after the monastery cut off electricity and water supply, former residents said. The fire spared Sergeeva's apartment, but in July, bailiffs broke in while she and her son were in hospital - and confiscated their belongings.

Valaam's last secular mayor and ex-firefighter Sergei Grigoriev says that the fire was an "arson organised by the monastery". One of the hotel's former residents, Dmitry Sinitsa, is awaiting trial on arson charges, but maintains his innocence and suspects monastery workers set the building alight.

"They solved the monastery's problems [with the resettlement] at once," Sinitsa says.

Back in 2005, Grigoriev shook hands with Putin on Valaam - and complained to him about the evictions. He was soon forced to resign and was evicted from his apartment.

"That handshake cost me dearly," says the gaunt 60-year-old who now lives in the mainland town of Sortavala. "I am a deported bum now."

Religious stronghold

The monastery's press service declined to provide comment and referred Al Jazeera to Bishop Pancraty's interview with the RIA Novosti news agency in July where he said: "Someone is always unhappy with a resettlement."

The Patriarchate's press service was not available for comment despite numerous requests.

Fewer than 100 monks live on Valaam now; some in secluded houses with saunas and garages with SUVs. Since 1991, the island's secular population went down from 550 to about 50.

"The objective is to only have the monastery on the island," Patriarchate spokesman Alexander Volkov told the Novaya Gazeta daily in mid-July. "Understandably, certain complications emerge, and it is hard to assume that everything will go on painlessly."

Valaam's only public school and hospital were closed last year, and Patriarch Kirill - who called the secular islanders' problems "microscopic" - ordered the razing of food and souvenir shops catering to pilgrims and tourists. Now, all that is available to the more than 100,000 people who visit the island each year are the basic, monastery-run rooms and shops.

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More confiscated properties

Elsewhere in Russia, restitution continues.

The Patriarchate seeks to seize a former barrack that was privatised by the family of a 90-year-old WWII veteran in the southern city of Stavropol; the land it stands on once belonged to a monastery.

The entire fortified medieval centre of the central city of Ryazan will become church property in 2018. Ruins of a 17th-century church and a nearby necropolis there were razed in July to give way to a new church; graveyard bones and debris were hauled to a junkyard.

After being transferred to the Patriarchate, 16 churches of a splinter Orthodox group in the city of Suzdal stand vacant, their newly painted frescoes crumbling.

In 2010, authorities in Kaliningrad, Russia's westernmost province that was part of Germany until 1945, transferred five castles dating back to the Crusades and almost 30 Catholic and Protestant buildings.

Orthodox clerics "accidentally" destroyed the frescoes in the 1364 Arnau church that were restored by a German charity for 450,000 euros.

"They are doing it under the banners of the 'Orthodoxification' of Kaliningrad," Mitrokhin says.

One of the five-storey buildings of the Russian Research Institute of Fisheries and Oceanography in northern Moscow stands on the foundation of a destroyed convent. A court ordered the entire institute to relocate despite the imminent destruction of sophisticated aquariums housing endangered salmon species.

"The institute's building will be destroyed," Kseniya Chernega, the Patriarchate's chief lawyer, told an appeals court in January. "A church will be rebuilt in its place."