Isaac Grünewald is an icon in Swedish art history. His works possess that kind of inherent energy that never seems to settle down. The unfathomable breadth of his production, the life and passion from which the countless projects were born, lives on and vibrates even today, without losing strength.

The story of the young, brash, and talented boy who went to Paris (1908 - 1911) to apprentice with the hedonist Henri Matisse is one of the 20th century's favourite tales in the realm of art in Sweden. Isaac described his first encounter with Matisse's painting as an explosion of colour: "Suddenly, I stood before a wall that sang, no, roared with colour and radiant light. Here I was confronted with something entirely new and ruthless in its unrestrained freedom." This freedom appealed to Grünewald, and he quickly enrolled in Matisse's prestigious painting school, which attracted many of the era's leading artists with its radical approach. With Matisse as a guide, Grünewald's painting underwent a significant development during the 1910s. This period is considered the pinnacle of his artistic production.

Under Matisse's influence, Grünewald and the other Swedish students left behind the Nordic colour palette and restrained brushwork, transitioning to an expressive colour scale and dramatic forms. Isaac Grünewald and Sigrid Hjertén, his future wife, became the leading figures of the groundbreaking expressionism that would fundamentally change Swedish art history.