Tidbit Tuesday-British Citizenship

In Smuggler's Captain, Nadia is neither a natural born British Citizen nor a naturalized one. As an unmarried woman, she does not have her husband's protection and her father has ever sworn allegiance to King George III.  

From the very long but informative Wiki article:

Individuals born in the dominion were citizens regardless of the status of their parents: children born to visitors or foreigners acquired citizenship (see Jus soli). This reflects the rationale of natural-born citizenship: that citizenship was acquired because British-born subjects would have a ‘natural allegiance’ to the crown as a ‘debt of gratitude’ to the crown for protecting them through infancy. Therefore, citizenship by birth was perpetual and could not be, at common law, removed or revoked regardless of residency.

By the same reasoning, an ‘alien’, or foreign born resident, was seen as unable to revoke their relationship with their place of birth. Therefore, at English common law foreign-born individuals could not become citizens through any procedure or ceremony.

So yes, Nadia's father could have sworn allegiance to the British Crown, becoming a British denizen (subject but not citizen) and unable to hold office. Doing so required the king to grant him a patent. Or he could have petitioned Parliament to grant him (and therefore Nadia) naturalisation, but frankly, neither Nadia nor her father really wanted the attention. Nor did those bringing her into the country, Kaya and Paul for their own reasons. 

Other resources: British National Archives and The British Home Office.