Though I have never studied English in school in my native country, I had been exposed through entertainment (by which I mean mostly movies and music). My father also helped me with a few attempts to learn English with a private tutor, which fizzled for one reason or another. When it became clear that I was going to leave for Canada, I joined British Council and made use of their books and tapes, which helped with my transition once in Toronto.
The circumstances of my learning influenced my language skills: because I learned mostly from reading, my reading and writing were above average, but my conversational abilities were underwhelming. Later on, after suffering a concussion, the progress I had made through immersion seemed somehow intermittently reset.
Of the languages I learned, this is probably the most "democratic". English language scholars have always made an effort to research and document common parlance and spoken English and include it in dictionary and treatises, rather than impose rigid rules through a top-down approach. English has also adopted a remarkably high number of Latin and even French locutions.
There is also a very low "grammar burden". The major difficulty in achieving fluency is pronunciation, but even that isn't really an issue, since the vast geographic span of this language guarantees a diversity of accents even among native speakers. I speak English with a bit of an accent and I'm quite happy this way, insofar as my slight accent provides some contextual background, which is often an opportunity to start a deeper conversation.
I have come to associate two institutions that played an important role in my becoming with this language: debating and the public library system. Libraries existed long before the first British library was built, but having learned English in a "library" and having been so amazed by the Toronto Public Library system, after having had the experience of the far less developed and less user-friendly system in my native country, I will always carry a debt of gratitude to this institution. Likewise, oratory may have been associated with Athenian Democracy, but I have known it mostly in its "British/Canadian Parliamentary" incarnation, through my membership in the Hart House Debating Club (w, f) and participation in the CUSID tournaments. I have come to see debating as essential for a democratic and open society.
(This was a Language I studied.)