Four months ago, addressing Polish strikers at the Lenin Shipyard, Lech Walesa made a solemn promise: On Dec. 16, the 10th anniversary of riots along the Baltic coast, they would all meet to commemorate friends, colleagues, and relatives killed by the government militia.

"And if I'm not there with you, you'll know where I'll be," he added.

There was a roar of applause and laughter. The occupation of the shipyard was only in its first week, and the outcome still far from certain, but the workers appreciated the mixture of defiance and cheek displayed by their strike leader.

Walesa, now head of Solidarity, the first independent trade union in the communist world, will be at the appointed place Tuesday to unveil a monument to the dead. So, too, will Communist Party officials, government ministers, church leaders, foreign ambassadors, journalists from all over the world and hundreds of thousands of ordinary Poles.

The huge and formal nature of the ceremonies is a reminder of how much Poland has changed as a result of the unrest of the last few months. But it is also a reminder of the fact that December 1970 marked a turning point in Poland's postwar history. The balance of political power shifted decisively in favor of the workers.

Many Poles are convinced that this year's peaceful worker rebellion was only made possible by that bloody December week. When strikes erupted in Poland last July, triggered once again by a rise in meat prices, the communist authorities decided at the outset that the crisis could only be solved by negotiation. It was a crucial decision, and it was made in large part because of the bitter memories of events 10 years ago.

For their part, the strike leaders were determined not to allow the unrest to spill over into the streets. In 1970, angry crowds of workers marched on Communist Party headquarters, demanding vengeance and burning public buildings in their path. This time they waited patiently inside their factories until the government was willing to talk.

The workers' riots of December 1970 led to the fall from power of the then Polish leader, Wladyslaw Gomulka, and his replacement by Edward Gierek. But it has taken a decade for the authorities to agree to the erection of a monument to the fallen shipyard workers, despite repeated demands.

Designed and built in four months at a cost of nearly $1 million, the monument now forms part of the Gdansk skyline. Three 120-foot-high crosses mingle with the cranes and apartment blocs of the waterfront. The crosses symbolize the soaring hopes released by Poland's three major post-war upheavals: 1980, 1970 and 1956, when the Stalinist regime was toppled by a workers' uprising in the western city of Poznan.

Next to the monument, inscribed on the wall of the shipyard, are the words: "They gave their lives so that we may live in dignity."