Modernist bronze sculptures, emerging in the late 19th and early 20th centuries, broke away from traditional artistic conventions to explore bold new themes. One of the most prevalent themes is abstraction, where artists like Constantin Brâncuși simplified forms to their essence, creating works such as "Bird in Space" that evoke movement and purity. Another common theme is the human condition, with sculptors like Alberto Giacometti depicting elongated, fragile figures to reflect existential angst and isolation.

Nature and organic forms also played a significant role, as seen in the works of Henry Moore, who blended human and natural shapes to suggest unity and growth. Additionally, many modernist bronze sculptures tackled themes of industrialization and modernity, with artists like Umberto Boccioni capturing dynamic energy and mechanical motion in pieces such as "Unique Forms of Continuity in Space."

Finally, spirituality and mythology were recurring motifs, with sculptors like Jacques Lipchitz drawing on cultural symbols to explore universal truths. Through these themes, modernist bronze sculptures became a powerful medium for expressing complex ideas and emotions, leaving a lasting legacy in the art world.