Like in every game in the series, the lore of Dark Souls II is cryptic and obscured. Lucky for us, the Lore in a Minute guys have our back.
Some spoilers ahead.
Lore in a Minute teamed up with Dark Souls fan and video creator VaatiVidya to break down the basic events that lead to Dark Souls II. It is a pretty solid breakdown, although as with most things Souls-related, some of it is predicated on conjecture and subject to revision with DLC.
via Lore in a Minute