>How far does loyalty to one's Sovereign extend? If someone is born under one Monarch, moves to a country with a different one, and becomes a citizen there, do they still owe any loyalty to their original Sovereign?
Sounds like a personal resolve. The loyalist spirit maintains a somewhat sanguine bond with their monarch. I doubt anyone else would care, but origin does matter.
>Would they only owe fealty if they specifically made an oath to their Sovereign?
Oath is an oath.
>A few years ago in my country, the courts ruled to allow new citizens to immediately recant the Oath of Allegiance they just made to become a citizen. What do you think of this?
Not surprised. They value revolution and destruction.