Glory of Portugal--Finding Sea Route to East : Exploration: Albuquerque was the first to wrest the Indian Ocean trade from the Muslims and control gateways to the lands of Columbus’ desire.

It was an astonishing empire, built 500 years ago by Portuguese pioneers, men like Dias, Da Gama, Cabral, Albuquerque, Magellan and others less renowned but no less bold.

They braved seas no European had sailed before to reach and exploit the Indies, the Spice Islands, Japan and China--precisely the shimmering goals Christopher Columbus sought--and died believing he had found.

In the 1992 quincentennial year, with all eyes focused on Columbus and America, Merle Severy traveled in the opposite direction, following the paths of the Portuguese explorers.

“For a century and more, these men of Portugal held in their grasp the rich seaborne trade of the East,” Severy wrote in a recent issue of the National Geographic.

“And long after their chain of Asian colonies--the first global empire--had crumbled into history, I would find their living imprint across half the world, from Morocco to Macao.”

To tell the story of Portugal’s nearly 600-year global encounter, which changed the world we live in today, Severy first made a pilgrimage to the spacious harbor of Lisbon, the capital. Here galleons set forth amid the roar of cannon and the braying of trumpets.

Seventy miles north at Tomar, Severy strolled the monastic corridors where Prince Henry, later celebrated as the Navigator, headed the Order of Christ; its revenues supported forays down the African coast.

While Henry and other Portuguese explorers are household names in the West, few Westerners know of Afonso de Albuquerque, empire builder of the East, whose feats led his countrymen to call him Afonso the Great.

First sailing east in 1503, this soldier and strategist capped the Portuguese discoveries with an empire that wrested Indian Ocean trade from the Muslims and controlled gateways to the lands of Columbus’ desire.

It was Albuquerque who in 1510 conquered Goa in western India, which he made the kingpin of Portuguese Asia. In 1511 came Malacca, Malaysia, key to eastern Asia, where the Indian Ocean funnels to the China Seas and eastward to the Spice Islands.

From Malacca, Albuquerque sent Francisco Serrao, possibly with his friend Magellan, to discover the source of spices in the Moluccas, the Spice Islands of eastern Indonesia. Then he sent embassies to Siam and to China.

It was King John II who truly launched Portugal’s great age of exploration. In 1482 and again in 1485, he sent his courtier Diogo Cao southward along the coast of Africa, where Cao discovered the mighty Congo River.

In 1487 John dispatched Bartolomeu Dias to round Africa in search of a route to the East. Dias returned in triumph.

Ultimately the Portuguese became part of the fabric of Eastern culture. “The secret of their survival was accommodation and collaboration,” Prof. Dejanirah Couto of the Sorbonne in Paris told Severy.

A living landmark of the Portuguese in Japan is mighty Nagasaki itself; they chose its site in 1570 on the invitation of the daimyo (regional lord) of Omura, a Christian convert.

A Christian settlement grew around the port, which became a hub of the rich Goa-Macao-Nagasaki trade. Portuguese-flavored in speech and food as well as faith, Nagasaki was a conduit for Western influence on Japan, from medicine to maps.

Portugal’s world empire began, and its resplendent days ended, with crusades in Morocco, only a few miles apart.

At Ksar el Kebir, 163 years after Prince Henry the Navigator won his spurs at Ceuta, King Sebastian, obsessed with quixotic dreams of knight-errantry, died with his army--leading to the takeover of his kingdom by his uncle Philip II and 60 years of “Spanish captivity.”

Portugal emerged with its manpower sapped by Spain and much of its empire taken by the Dutch and English enemies of imperial Spain.

Yet Goa, last vestige of Da Gama and Albuquerque’s Portuguese India, held out until 1961. When Macao reverts to China in 1999, the first colonial power in Asia will be the last to go.

Severy asked Mario Soares, president of the Republic of Portugal, how he’d sum up Portugal’s global encounter.

“Portugal’s navigators,” Soares replied, “showing Europe the way across the oceans, brought back more than spices, gold, precious stones and silk. They interacted with ancient cultures and gave us the vision of the one world we have today.

“At the close of the cycle of empire, as we enter universal civilization, Portugal will remain, as our poet Fernando Pessoa saw it, ‘the face of Europe that looks out to the rest of the world.’ ”