During a pomp-filled ceremony broadcast live on television, the 42-year-old placed his hand on a red, leather-bound copy of the Russian Constitution to take the oath of office.
He told the 2,000 dignitaries packed in the Kremlin's gold-leafed Andreyevsky Hall that he would do his best to bolster the country's economic development and civil rights.
"I consider my most important task to be the further development of civil and economic freedoms, the creation of the broadest new opportunities for the self-realization of citizens -- citizens who are free and responsible both for their own success and for the well-being of the whole country," Medvedev pledged.
Putin, who named Medvedev as his preferred successor in December, thanked the Russian people for their support and wished Medevedev well.
Aleksy II, the patriarch of the Russian Orthodox Church, also delivered a brief speech in which he wished the new Russian leader "wisdom, endurance, inspiration, and blessed success."
Following the spectacle, Medvedev and Putin descended into the Kremlin's courtyard, where they were saluted by the presidential guard.
The ceremony to seat Medvedev was the fifth of its kind since Boris Yeltsin, Russia's first popularly elected president, took office in 1991.
Yeltsin's first inauguration ceremony, however, was an improvised affair. Yeltsin read his oath of office at a regular session of the Congress of Russian People's Deputies, held on the Kremlin grounds under the icy stare of Soviet President Mikhail Gorbachev.
Unlike his successors, Yeltsin was not ushered ceremoniously into the hall where he was to take his oath; he simply walked up from his seat in the squat building where Soviet-era Communist Party congresses used to be held.
After reciting his oath, Yeltsin took a seat at a table on the stage. Patriarch Aleksy II then took his turn at the microphone. But instead of the usual words of congratulation, it was a stern warning the patriarch delivered to the assembled dignitaries.
"There is no point today looking for incarnations of evil in our country and assuming that their removal from the political scene will automatically solve everything," Aleksy warned Yeltsin and his fellow Russians.
Five years later, Yeltsin's second presidential inauguration was equally spartan.
Since by then the Soviet Union was no more, the text of the oath had changed. The president -- who had recently been hospitalized twice for heart disease and had not appeared publicly for weeks -- had changed, too.
"I swear that in exercising the powers of the president of the Russian Federation," a visibly shaky Yeltsin slurred as he took his oath of office, "I shall respect and protect human and civil rights and freedoms, observe and protect the Constitution of the Russian Federation, protect the sovereignty and independence, security and integrity of the state, and faithfully serve the people."
The entire ceremony, which included fanfare, a military salute, and the by-now traditional address by Aleksy, lasted a mere 16 minutes. One of the two planned receptions was canceled at the last minute.
Putin On Parade
Yeltsin's successor, Vladimir Putin, by contrast, was inaugurated with great pomp in the lavish Kremlin Palace. The former KGB officer walked on a red carpet through the restored Kremlin halls before reaching a small podium where he took his oath -- and pronounced what became the first inauguration speech by a post-Soviet Russian president.
Putin's address made a particular emphasis on the word "democracy."
"The path to a free society was neither smooth nor easy. There have been both tragic and bright chapters in our history," Putin said. "The construction of a democratic government is far from completed, but much has been done. We have a duty to uphold what was achieved, to defend and promote democracy, to ensure that the authorities elected by the people serve the people's interests."
His second inauguration speech in 2004 made only fleeting references to democracy and freedom, focusing instead on political stability and economic development.
And while he referred to the "tragic chapters" of Russia's history in 2000, Putin's second inauguration address described these very pages only as "glorious."
"We are the heirs of a 1,000-year-old Russia, the motherland of outstanding sons and daughters, toilers, warriors, creators. They left us a vast, great nation," Putin said. "Our past unquestionably gives us strength. But even the most glorious history cannot alone guarantee us a better life."
But unlike his predecessors, Putin will retain major influence after stepping down as president.
Putin has already been named prime minister by Medvedev -- he is due to be confirmed by the State Duma as soon as May 8 -- and was recently appointed leader of the ruling Unified Russia party.
Medevedev's inauguration ceremony, throughout which he stood shoulder to shoulder with his mentor, was a powerful statement that Putin is still a force to be reckoned with.