Simplify the following text for a Grade 11 native English-speaking person.
Original: Later on in the Kamakura period , Kamakura Shogunate forces emperors Gotoba and Emperor Godaigo to exile to Oki .
Simplified: Later on in the Kamakura period , the Kamakura Shogunate forced Emperor Gotoba and Emperor Godaigo into exile on Oki Island .