Dmitry Medvedev was sworn in as president in a solemn ceremony in the Kremlin's throne room on Wednesday, ushering in an unprecedented period of dual rule with his predecessor Vladimir Putin, who becomes prime minister.
Medvedev, a 42-year-old former corporate lawyer and longtime Putin ally, placed his hand on a red, leather-bound copy of the Russian constitution to take the oath of office before 2,000 invited guests.
Minutes earlier, Putin had entered the Kremlin alone and thanked the Russian people for their trust and support, encouraging them to support Medvedev and wishing him well.
He stressed freedom and the rule of law in his first remarks after taking the oath of office in a solemn, emotional ceremony in the Kremlin's glittering St Andrew's Hall.
"I believe my most important aims will be to protect civil and economic freedoms," he told guests at the inauguration, broadcast live on state television.
"We must fight for a true respect of the law and overcome legal nihilism, which seriously hampers modern development."
Putin named Medvedev as his preferred successor last December, ensuring his victory in the March polls.
While the ceremony resembled Putin's first inauguration in 2000, it marks a profound difference beneath the pomp. Putin took over from the ailing and unpopular Boris Yeltsin, who had handed Putin power months earlier.
Prime minister Putin
Putin will retain major political influence after quitting, both in his role as prime minister and as head of the ruling United Russia party which controls parliament.
The inauguration ceremony in the Grand Kremlin Palace broadly followed the pattern set in 2000, allowing officials to stress continuity and the smooth transition of power. Access was not granted to foreign media.
The constitution, adopted under Yeltsin, gives the president strong powers, including the right to define Russia's foreign and domestic policy, appoint key ministers and control key security and defense agencies.
Putin, in his time in office, further boosted Kremlin power by assuming the right to name hitherto elected regional leaders and taking control of parliament.
Putin has said he sees no problem working with Medvedev with whom he shares common views on Russia's future. But Russia's history, dominated by single powerful rulers such as Josef Stalin and the Tsars, knows few examples of smooth co-existence.
Short-lived rivalries between Yeltsin and his powerful prime ministers usually ended in the resignations of the latter.
Putin has preferred technical, and weak, premiers. But when he is confirmed as a new prime minister by parliament on Thursday and lands in his new riverside office in central Moscow, the picture is sure to change dramatically.
Putin, who has presided over eight years of uninterrupted economic growth, has said he will focus on making Russia one of the top seven global economies by 2020. He has promised not to seek any extra powers in his new job.
Eight years ago, the departing Yeltsin left Putin a pen with which he used to sign laws as a symbol of a handover of power. Putin said in a newspaper interview last month, he would take the historic pen with him rather than leave it to Medvedev.
Victory Day parade
Medvedev's inauguration will be followed Friday by a Victory Day parade celebrating the Allied defeat of Nazi Germany in World War II, with tanks and missile launchers rolling across Red Square for the first time since the Soviet Union's 1991 collapse.
While the military parade will evoke memories of Soviet military glory, the inauguration ceremony will was expected to be more reminiscent of imperial Russia's grandeur.
Putin was the first president to take the oath in the Grand Kremlin Palace, which has been restored since the Soviet collapse. Yeltsin, and the last Soviet leader, Mikhail Gorbachev, were inaugurated elsewhere on the Kremlin grounds — in the boxy modern building where Soviet-era Communist Party congresses were held.
Among the 2,000 invited guests are Gorbachev, Yeltsin's widow, Naina, and a host of foreign ambassadors, as well as Russian lawmakers, religious leaders and prominent figures from the arts, business and other circles.
Amid preparations for the inauguration and military parade, central streets have been closed intermittently, compounding Moscow's already notorious traffic troubles, thickening rush-hour subway crowds.