Does the foundation laid by 'After the purge of foreigners, only a few stayed on, strictly confined to Dejima Island in Nagasaki Bay.' logically support 'A few foreigners were confined to Dejima Island because they were dangerous.'
After the purge of foreigners, only a few stayed on, strictly confined to Dejima Island in Nagasaki Bay.###A few foreigners were confined to Dejima Island because they were dangerous.