Milan Mrkusich was born in Dargaville to Dalmation parents. In 1927, he moved with his family to Tāmaki Makaurau. From 1942, he was apprenticed to a graphic designer. He learned lettering and pictorial arts, attending night classes at Seddon Technical College with the aim of becoming a commercial artist.
It was during his apprenticeship that Mrkusich became disillusioned about the career in store for him. Reading the magazine Arts & Architecture, he became fascinated by critical writing about painting and music and he resolved to become an artist—not a landscape artist of the type fostered during those years at Elam School of Fine Arts or the Auckland Society of Arts, but an abstract painter.
Mrkusich was much more interested in the European modernism of Piet Mondrian, Wassily Kandinsky, and the Russian Constructivists than in the fashionable quest for a truly New Zealand (i.e. non-British) art based on the landscape. In this, he was to be far more encouraged by young Auckland architects than by other painters. In 1949, with two architects, Des Mullin and Steve Jelicich, he set up the shop Brenner Associates, where modern art, ceramics, and furniture were sold to people who wanted to live among contemporary objects.
Since 1946, Mrkusich had been painting abstract works. Few of the paintings sold, but, like Colin McCahon, he did manage to find a group of people adventurous enough in their taste to support his efforts. By 1958, he was ready to take the risk of trying to make a living as a full-time painter. Despite considerable initial hardship and discouragement, he is now regarded as one of Aotearoa’s foremost painters.