Georgia on Sunday was to mark the fifth anniversary of the peaceful pro-Western "Rose Revolution" under the shadow of a war with Russia that has left the country's future precariously uncertain.
Five years after President Mikheil Saakashvili swept to power after leading the nonviolent revolt in the ex-Soviet republic, the anniversary was also to highlight increasing challenges to his rule.
Opposition supporters were to protest outside the offices of the Imedi television channel, a media outlet they say has been muzzled for criticising the authorities.
And a key ex-ally of Saakashvili, former speaker of parliament Nino Burjanadze, was set to found a new opposition political party aimed at pushing him out of power.
Official celebrations were to be kept low-key, with the only planned event being a concert at Tbilisi's ornate opera house.
In a nationally televised address late Saturday, Saakashvili called for Georgians to unite as they did during the revolution against a "dangerous threat" from Russia.
"We were attacked because of the success of the last five years, it was the last challenge of the empire against us," he said.
"We have never faced such a dangerous threat. We need strength and unity. We must believe in the future and have courage. Instead of celebrating tomorrow, we must show unity as we did on November 23, 2003."
In a statement released Saturday before he was to hold talks with Russian President Dmitry Medvedev, US President George W. Bush hailed the revolution and vowed continued support for Georgia.
"On this anniversary, Americans honor the brave Georgian citizens who defended freedom, and we renew our commitment to supporting Georgia's democracy, independence, sovereignty, and territorial integrity," Bush said.
The Rose Revolution saw tens of thousands of protesters rally in Tbilisi in November 2003 to denounce parliamentary elections won by allies of then-president Eduard Shevardnadze.
The veteran Georgian leader resigned on November 23 after protesters, led by Saakashvili brandishing a single rose, stormed into parliament.
Backed by Western governments, in particular Washington, Saakashvili began widespread reforms and vowed to bring Georgia into NATO and the European Union.
He tackled corruption and attracted record levels of foreign investment, helping Georgia's economy reach a growth rate of 12 percent in 2007.
But in recent years critics have accused Saakashvili of becoming authoritarian, especially after riot police violently dispersed tens of thousands of anti-government protesters last year.
He is also coming under increasing criticism for the government's handling of the August war, which saw Russian troops pour into Georgia to repel a military attempt to retake the Moscow-backed rebel region of South Ossetia.
Moscow's subsequent recognition of South Ossetia and another separatist region, Abkhazia, as independent states has made Georgia's goal of regaining control of the rebel areas all but impossible.
The war also set Georgia back in its efforts to build closer ties with the West. Despite promises of substantial aid and condemnation of Russia's actions, Western leaders have given only lukewarm support to Saakashvili.
Earlier this month, the EU agreed to resume frozen talks on a new strategic pact with Russia over strong Georgian objections.
Western politicians, media and rights groups have also raised concerns over the conduct of the war, accusing both Georgia and Russia of having indiscriminately targeted civilians.