Lassen received little formal education in the arts, but his mother Carol was artistically talented and she encouraged her son’s interest. Lassen had some early success designing T-shirts and selling some paintings in a small shop, but didn’t develop much national acclaim as a painter until Jona-Marie Price began marketing his work for him. His popularity rose when he began selling his first series of limited edition paintings, and soon he was selling overseas as well.

Lassen’s love of nature has made him a passionate environmentalist. He is a frequent speaker in both the United States and Japan on the preservation and protection of world oceans. In 1990 Lassen established the Seavision Foundation, a non-profit organization that supports a number of ocean-related environmentalist projects. The foundation is supported in part by the sale of Lassen’s work. In 1992, in recognition of both his work as an environmentalist and his talent as a painter, the United Nations commissioned him to design their official stamp commemorating ocean preservation.

In addition to his painting, Christian Riese Lassen is a professional surfer. Before his career as an artist was fully established, he gained some measure of national and international acclaim as a surfer, appearing on billboards and in magazines, as well as television and movies.

Although he is best known for his seascapes, Lassen has experimented with a number of different subjects, including other natural themes, mythology, and pop culture. He has also dabbled in a wide variety of artistic styles, from glazing in the style of the old dutch masters to impressionism and pop and abstract art. Nonetheless, all of his painting carry his signature blend of luminescence and attention to detail, making them highly recognizable no matter what the subject or style.