Originally from Budapest, Hungary, Oscar came to Canada in 1981. His life's work of over 50 years was as a physician, but he has spent the last 15 years developing as a painter. Originally working with acrylics, he currently paints using oils mixed with cold wax, with the addition of oil pencils, markers, and pan pastels to create the colours he is drawn to. Koller joined Art 1274 Hollis in 2022. His work has also been shown at Artful Persuasion in Fredericton, New Brunswick.