A mokomokai is a prepared tattooed head of a deceased Maori. The preservation of tattooed heads was a tradition. First the brain was extracted, the eyes removed and all openings sealed with flax fibers and resin. Then the head was boiled or steamed in the oven, smoked over an open fire, and dried in the sun for several days. Finally, it was treated with shark oil. Conservation caused the tattooing of the head and the face of the deceased to be maintained. Preserved heads were produced by chiefs, family members, enemies or slaves. Heads of relatives were preserved in carved wooden boxes and displayed on occasions. In Maori tradition, the human head was the most sacred part of the body and subject to tapu. That is, it was not to be touched. The Maori also associated magical powers with the mokomokai. The sacred head of a chief was the resting place of the ancestral spirit, which was communicated with by priests. The heads of enemies were placed on a wooden stick, erected and mocked. Because of the great interest in tattooed heads, the Maori also made them to order. For this purpose, people were killed and their mokomokai were sold to researchers, travelers and tourists.
It is believed that more than two hundred mokomokai are in museums, both in New Zealand and abroad. One came to the Vienna World Museum through the collector Johann Georg Schwarz, but this mokomokai was returned to New Zealand in 2015.