The primary culture, if the owner has achieved cultural union and the province neighbors a primary culture province.The primary culture, if it is the country's capital.Once the progress reaches 100, an event will fire changing the province's culture to:

Province conversion Event Mean Time to Happen (MTTH) Conversion progress is tracked separately per each province, its rate of increase is based on various factors. The country's primary and accepted cultures will continuously spread by adjacency to state provinces without separatism.