For a long time, there were two ways to become an Australian citizen. The first, the trickier but paradoxically much the more common method, was to find your way into an Australian womb and wait for nine months.
The other way was to get an assisted passage out by signing an undertaking to stay for at least two years ...
... and then wait for five years ...
... or having it reduced to three by sitting for a dictation test ...
... after which you swore an oath of allegiance.
All this happened at the other end of my life, when I was still quite young, nineteen going on twenty. Having become an Australian the other way, English was never my mother tongue but it became my adopted tongue. As I read Bill Bryson's book, I'm surprised it happened at all.