The Oceans Past Initiative (OPI) is a global research network for marine historical research. Our goal is to enhance knowledge and understanding of how the diversity, distribution and abundance of marine life in the world’s oceans has changed over the long term to better indicate future changes and possibilities. OPI welcomes anyone from any culture interested in the history of humankind’s interactions with life in the oceans, including scholars from all disciplines, marine policy makers and managers, and Indigenous knowledge holders.