Sebestian received his BSc in Biology from the University of St Andrews in 2014, where he developed an interest in Ethnobotany. Pursuing these interests, he completed his MPhil and PhD in the History of Science and Medicine at the University of Cambridge in 2015 and 2019, respectively. Focusing on the Philippines, Sebestian’s PhD traced the movements of natural and medical knowledge across three continents, from London and English colonial outposts in India to Dutch, Spanish and Portuguese settlements in Asia and the Americas. His dissertation was awarded the 2020 Santorio Award for the best PhD in the History of Science and Medicine.
Following his PhD, Sebestian joined the Renaissance Skin Project at King’s College London, funded by the Wellcome Trust. By focusing on skin colour, skin diseases and skin marking, he examined the role of skin in constructing and challenging cultural, social, and gendered hierarchies in colonial spaces in the Pacific Rim. In 2021, he organised a workshop Tattooed Bodies in Early Modern Worlds on the histories and decolonisation of tattooing practices.
Sebestian has published on indigenous tattooing in the Philippines, long-distance networks of knowledge exchange and Renaissance geography, and co-edited a special issue of the British Journal for the History of Science on science and islands in Indo-Pacific worlds. He participated in the Making and Knowing Project at Columbia University (2016-2017), during which he helped transcribe, translate, and encode a sixteenth-century French artisanal manuscript. He was affiliated with the Natural History Museum in London, where he catalogued its early modern Philippine collections (2017-2018). Sebestian is a member of the British Society for the History of Science, British Society for the History of Pharmacy, Pacific Circle, and Renaissance Society of America.