This thesis looks at illegal public art produced on state built barrier walls. The focus is on the artist Ron English, and his artworks produced on the Berlin Wall, Israeli Barrier Wall, and Mexican Border Fence. I examine English’s works in their respective contexts of Cold War divisions, the Israeli/Palestinian conflict, and tensions at the border between United States and Mexico. I also situate English’s works in relation to other artworks produced on these barriers. I argue that English is doing something different from other barrier wall artists in his work in Palestine and Mexico, offering a framework for understanding the primary motivations and tactics behind barrier wall art and highlighting English’s unique contributions.