The traditional day of welcoming spring, originally by garlanded dancers circling a Maypole, has evolved more recently into an international labor holiday.
But with the growing antiglobalization movement, the celebrations have turned increasingly into demonstrations for workers' rights, a la Seattle, Prague, and Quebec City.
Yesterday, German police turned water cannon on leftists in May Day street battles, activists targeted Australia's stock exchanges, and in London, massed ranks of cyclists brought chaos to rush-hour traffic.
Protesters complain that multinational corporations wield too much power over people's lives, even to the point of coercing democratically elected governments.
About 20,000 workers faced 15,000 riot police on the streets of Seoul, South Korea's capital, to protest government-initiated economic restructuring and a harsh police crackdown on Daewoo Motor workers in April.
In Taiwan, thousands of unemployed workers and union activists marched through Taipei, demanding jobs and the resignation of top government officials.
The Russian news agency Interfax said more than 50,000 people took part in May Day rallies across Siberia and the Far East. It said they were demanding higher wages, better working conditions, improved pensions, price controls, and abolition of a single social tax introduced at the beginning of the year.
Berlin police turned water cannon on thousands of protesters after being pelted by bottles and stones.
In Australia, protesters blocked streets in financial districts and marched on state parliaments in Sydney and Melbourne.
In Britain, police deployed in force across London to face an estimated 10,000 activists, vowing to prevent a re-run of the violence that erupted in the city a year ago.
More than 500 cyclists blocked rush-hour traffic as they made their way slowly through the streets and stopped briefly outside the the US Embassy to stage a noisy protest.
Shops in the British capital boarded up windows to deter looters, and monuments such as the statue of wartime leader Winston Churchill were covered to prevent them being defaced.
Banks told employees to dress casually, to leave gold watches at home, and not to carry laptop computers.
Along with New York and Tokyo, London, with a population of 7 million, is 1 of the 3 leading financial centers in the world, and has the largest share of trading in many markets.
In Zimbabwe, thousands of workers gathered for a rally seen as a test of the government's ability to win key labor votes ahead of next year's presidential polls.
In Hong Kong, hundreds of workers staged protests against high unemployment.
In Greece, flights were curtailed and shipping and rail services disrupted when public transport workers joined in protests against government plans for pension changes.
A scuffle broke out in the northern Italian city of Turin after a small group of activists backing center-right leader Silvio Berlusconi tried to join a leftist May Day rally.
Some 5,000 mostly elderly supporters of Bulgaria's main opposition Socialist Party marched in central Sofia to protest against poverty, rising crime and corruption.
(c) Copyright 2001. The Christian Science Monitor