Apollonio was born in 1935 in Bertoki near Koper. His formative years were spent in his hometown among vineyards and the shallow waters of the Gulf of Koper, where he was captivated by the colors and forms of the Mediterranean environment—a lifelong inspiration. In 1955, Apollonio graduated from the Slovenian High School in Koper and passed the entrance exam to the Academy of Fine Arts in Ljubljana. He studied painting under Slavko Pengov, Riko Debenjak, Marij Pregelj, and Maksim Sedej. He graduated in 1960 under Gabrijel Stupica and continued with postgraduate studies in painting under him, which he completed in 1964. During his student years, he visited Paris for the first time and wandered through Provence, which strongly reminded him of his native Istria. In van Gogh’s Arles, he witnessed a bullfight, experiencing its vibrant and bloodstained ceremony. This event profoundly influenced the young artist. A few years after graduation, he decided to pursue a career as an independent artist. Travelling extensively through Italy, Spain, the Netherlands, and France, he admired the works of Michelangelo, Tintoretto, El Greco, Velázquez, Goya, Rembrandt, Rubens, Renoir, and Picasso. Back in his studio in Koper, he sought his own artistic language in graphics and painting, particularly drawn to serigraphy (screen printing), a technique then little known and practiced in Slovenia. The Academy of Fine Arts in Ljubljana invited him to organize a serigraphy program. After a brief stint as an assistant to Professor Gabrijel Stupica, he was promoted to docent, associate professor, and later full professor. He served as the head of the Graphics Department and as vice-dean of the academy for four years.

In his biography, he wrote about himself:
“I believe that the time and place of my birth (May 15, 1935, in Bertoki near Koper) are not mere coincidences but significant factors that have profoundly impacted my life since childhood. I was born under the sign of Taurus, a mythical and earthly creature full of life drive, tragedy, kindness, naivety, imbued with relentless perseverance, and an insatiable longing for beauty, goodness, and pleasure. If this has marked my character traits, then the second fact, the place of my birth, marked my life path. Born in a place where history bestowed neither grace nor glory, just the harsh reality of everyday life between sea and shore, in a small village of humble, almost poor farmers who grew vines and olives. From my ancestral home, it’s only a stone’s throw to the sea. In summer, as children, we splashed in the shallow waters, chased crabs, caught fish, eels, and gathered shellfish. A dusty road from the village leads to the parish church and cemetery, where my prematurely deceased father, two brothers, and my mother Antonija—who survived all wars and the many states that passed through this region in the last century and died at 94—are buried. To her, I will always be grateful that all my journeys led me back home. Two of my sisters who went out into the world, like me, continually return home.”
Zvest Apollonio died on March 25, 2009, in Bertoki.