AMSTERDAM — Willem-Alexander became the first Dutch king in more than a century today as his mother, Beatrix, abdicated after 33 years as queen.

The generational change in the House of Orange-Nassau gave the Netherlands a moment of celebration, pageantry and brief respite as this trading nation of nearly 17 million struggles through a lengthy recession brought on by the European economic crisis.

Visibly emotional, the much-loved Beatrix ended her reign in a nationally televised signing ceremony as thousands of orange-clad people cheered outside. Millions more were expected to watch on television.

King Willem-Alexander, who became the youngest monarch in Europe, gripped his mother’s hand and looked briefly into her eyes after they both signed the abdication document in the Royal Palace on downtown Amsterdam’s Dam Square.

Beatrix looked close to tears as she then appeared on a balcony, decked out with tulips, roses and oranges, overlooking some 20,000 of her subjects.

“I am happy and grateful to introduce to you your new king, Willem-Alexander,” she told the cheering crowd.

Moments later, in a striking symbol of the generational shift, she left the balcony and King Willem-Alexander, his wife and three daughters — the children in matching yellow dresses and headbands — waved to the crowd.