Complex sentence: The state was based in Prussia after the Order's conquest of the Pagan Old Prussians which began in 1230, but also expanded to include the historic regions of Courland, Gotland, Livonia, Neumark, Pomerelia and Samogitia.
Split into simpler sentences: The state was based in Prussia after the Order's conquest of the Pagan Old Prussians which began in 1230. It expanded to include at various times Courland, Gotland, Livonia, Neumark, Pomerelia and Samogitia.