According to a popular Dutch theory, water has shaped the Dutch national identity. The Dutch fight against the water would have stimulated perseverance, ingenuity, cooperation and an egalitarian and democratic society. Despite the long water management history of the Netherlands, water became an important part of the self-images of the nation only in the eighteenth Century. In the 1780s the idea that the Dutch had wrung their country from the sea became popular. Initially, this idea was especially popular among the (proto-)liberal opposition, who emphasised the importance of the nation and its achievements. By the end of the nineteenth Century, water had become a national symbol for orthodox Calvinists, Roman Catholics and Socialists too, despite their different views on the nation. Whenever there was fast social change, political turmoil or external threats, as in the late eighteenth Century, the 1930s and 1940s and since the 1990s, the link between water and the Netherlands was used to promote national pride and unity and stimulate action. This link has also been used to promote specific hydraulic works, but it is a topic for further research how widespread and effective this practice was. As this paper is part of a special issue, Water History in the time of COVID-19, it has undergone modified peer review.