Japan has the world's third-largest economy, having achieved remarkable growth in the second half of the 20th Century after the devastation of World War II.
Its role in the international community is considerable. It is a major aid donor and a source of global capital and credit.
More than three quarters of the population live in sprawling cities on the coastal fringes of Japan's four mountainous, wooded islands.
Japan's rapid post-war expansion - propelled by highly successful car and consumer electronics industries - ran out of steam by the 1990s.
The 1997 Asian financial crisis, and bouts of recession, precipitated major banking, public spending and private sector reforms.
Japan remains a traditional society with strong social and employment hierarchies - Japanese men have tended to work for the same employer throughout their working lives.
But this and other traditions are under pressure as a young generation more in tune with Western culture and ideas grows up.
On the other hand, one of the biggest challenges that successive Japanese governments have faced is how to meet the huge social security costs engendered by an ageing society.
Japan's relations with its neighbours are still heavily influenced by the legacy of Japanese actions before and during World War II. Japan has found it difficult to accept and atone for its treatment of the citizens of countries it occupied.
A Japanese court caused outrage by overturning a compensation order for Korean women forced to work as sex slaves.
South Korea and China have also protested that Japanese school history books gloss over atrocities committed by the Japanese military. Japan has said China promotes an anti-Japanese view of history.
Following World War II, lawmakers forged a pacifist constitution. This seemed inviolable for more than half a century, but since the beginning of the twenty-first century it has been subjected to some reinterpretation.
In the last decade, some Japanese politicians have called for the constitution to be revised so as to enable the country to play a more active role on the world stage, and in particular to allow its military to take part in peacekeeping missions abroad.
Twenty percent of the world's earthquakes take place in Japan, which sits on the boundaries of at least three tectonic plates. Schools and office workers regularly take part in earthquake drills, and waiting for "the big one" is deeply engrained in the national psyche.
* Full name: Japan
* Population: 126.9 million (UN, 2010)
* Capital: Tokyo
* Area: 377,864 sq km (145,894 sq miles)
* Major language: Japanese
* Major religions: Shintoism, Buddhism
* Life expectancy: 80 years (men), 87 years (women) (UN)
* Monetary unit: yen
* Main exports: Vehicles, computer parts, chemicals, scientific instruments and watches
* GNI per capita: US $42,130 (World Bank, 2010)
* Internet domain: .jp
* International dialling code: +81
Head of state: Emperor Akihito
Akihito succeeded his father, Hirohito, in 1989. Under the 1947 constitution, Japan's emperors have a purely ceremonial role.
Prime minister: Yoshihiko Noda
Yoshihiko Noda became prime minister in August 2011 following the departure of Naoto Kan, who resigned following a brief premiership marred by economic gloom and a nuclear crisis triggered by the massive earthquake and tsunami that hit Japan in March 2011.
Mr Noda became Japan's sixth prime minister in five years, and the third premier since his centre-left Democratic Party of Japan (DPJ) came to power in August 2009 after winning a landslide election that ended half a century of conservative rule.
His predecessor, Naoto Kan, became prime minister in June 2010 following the resignation of Yukio Hatoyama amid a damaging dispute over an unpopular US air base off Okinawa.
Mr Noda inherits some daunting challenges from Mr Kan. Support for the DPJ rapidly ebbed away when it failed to rein in the country's huge public debt - which in August 2011 stood at twice the size of the economy - and the leadership's popularity ratings plummeted even further when it was perceived to be making heavy weather of the task of disaster recovery.
In his role as finance minister prior to becoming premier, Mr Noda pledged tough economic reforms to reduce the public debt mountain - the highest debt to GDP ratio in the industrialised world - and to pay for nuclear disaster relief by raising taxes rather than borrowing.
Unlike Mr Kan, who vowed to phase out nuclear power, he believes that the shut-down reactors should be restarted once they are deemed safe.
But perhaps his most immediate challenge is to unite the warring factions within the DPJ and to secure the support of opposition parties, which control the upper house and so have the power to block legislation.
Mr Noda grew up in Chiba, to the east of Tokyo. Unlike many Japanese lawmakers, he does not come from a political dynasty and indeed has relatively humble origins - his parents were both from poor farming families.
He has made much of his "ordinariness", insisting that reliability and stability are what Japan needs, not charisma and style.
From : BBC News