Is it true that the Japanese emperor is the only current emperor in the world?

 Yes, it is true that the Japanese emperor is the only current emperor in the world. Emperor Naruhito, who ascended the throne in May 2019, represents a tradition that dates back over a thousand years in Japan. The Japanese monarchy is considered the oldest continuous hereditary monarchy in the world.

The role of the emperor in Japan is largely ceremonial today, following the country's defeat in World War II and the subsequent changes to its constitution. The emperor's duties include attending cultural and public events, meeting foreign dignitaries, and performing traditional rituals. Despite having no political power, the emperor remains a significant cultural and spiritual figure in Japan.

Historically, emperors were common in various parts of the world, but most of these monarchies have either transitioned to different forms of government or have been abolished. The last significant imperial monarchies outside Japan, such as the Russian, Chinese, and Ethiopian empires, ended in the 20th century due to revolutions, wars, and political changes.

In modern times, the concept of an emperor has become rare, with most countries favoring republics or constitutional monarchies with kings and queens rather than emperors. The unique position of the Japanese emperor highlights the blend of tradition and modernity in Japan, maintaining an ancient institution within a contemporary state framework.

Therefore, the Japanese emperor's unique status as the only reigning emperor in the world underscores Japan's rich historical legacy and its ability to preserve its cultural heritage while adapting to modern governance and societal norms.