Bermuda was colonised by the English as an extension of Virginia and has long had close ties with the US Atlantic Seaboard and Canadian Maritimes as well as the UK. It had a history of African slavery, although Britain abolished it decades before the US. Since the 20th century, there has been considerable immigration to Bermuda from the West Indies, as well as continued immigration from Portuguese Atlantic islands. Unlike immigrants from British colonies in the West Indies, the latter immigrants have had greater difficulty in becoming permanent residents as they lacked British citizenship, mostly spoke no English, and required renewal of work permits to remain beyond an initial period. From the 1950s onwards, Bermuda relaxed its immigration laws, allowing increased immigration from Britain and Canada. Some Black politicians accused the government of using this device to counter the West Indian immigration of previous decades.