How did Broadway Boogie Woogie differ from Piet Mondrian’s earlier grid paintings?

In his earlier grid paintings, Piet Mondrian utilized a strict, austere structure characterized by black lines that intersected to form a grid, often balanced by discrete areas of primary color.123

In contrast, Broadway Boogie Woogie (1942–43) represents a significant departure from this approach, reflecting the influence of New York City’s vibrant energy and American music. The key differences include:1

• Replacement of Lines: Mondrian abandoned the continuous, austere black lines of his earlier work, replacing them first with colored bands and subsequently with a series of small, rhythmic rectangles.13
• Rhythmic Movement: Instead of a static grid, these small color blocks coalesce into a dynamic, "joyous" flow of vertical and horizontal lines.1
• Emphasis on Color: The work prioritizes the autonomous movement of color blocks over the rigid linear framework that defined his earlier Neoplasticism.12

These changes marked the final phase of Mondrian’s style, shifting from the severe, nonrepresentational constraints of his earlier period toward a more vivacious expression of rhythm and color.1