Rodinia was a massive supercontinent that assembled around 1.1 billion years ago during the Mesoproterozoic and Neoproterozoic eras, and began to break apart roughly 750 million years ago. Its name comes from the Russian word for 'birthplace' or 'homeland'. Rodinia stood at the center of the global ocean Mirovia, with North America (Laurentia) forming its core, surrounded by East Antarctica, Australia, Siberia, and Baltica. Tectonic rifting and the eventual breakup of Rodinia increased weathering on new coastlines, drawing down carbon dioxide and triggering the global Cryogenian 'Snowball Earth' glaciations.