Rise of the First Order is the shortest well-populated era on the chart and the one readers argue about most. It covers roughly seven years, three films, and a publishing programme that has spent a decade filling in the connective tissue those films left out — which is a polite way of saying that the books are doing load-bearing work here that the films did not do for themselves.
Where the First Order came from
Not from nothing. Canon establishes that Imperial officers, ships and resources withdrew into the Unknown Regions before and after the Battle of Jakku, following survey routes prepared years earlier, and rebuilt out of the New Republic's sight. The Galactic Concordance forbade exactly this. The Republic's response to evidence that it was happening anyway was to treat the accusation as warmongering, which is the era's whole political tragedy in one sentence.
Leia and the Resistance
The Resistance is not the New Republic's army. It is a private paramilitary founded in 28 ABY by a senator who lost the argument in the Senate and acted anyway — and whose political standing collapsed when her parentage became public. Claudia Gray's Bloodline (2016) is the essential text; without it the opening of The Force Awakens is much harder to parse, because the film never explains why the galaxy's legitimate government is not the one fighting.
The Jedi question
The era's real subject is inheritance and whether it is survivable. Luke Skywalker rebuilds the Order, loses it in a single night when his nephew burns the temple, and exiles himself. Rey is trained twice, briefly, by two masters who have both already failed. The films' answer — that the Jedi are an idea rather than a lineage, and that Rey takes the Skywalker name by choice rather than blood — is either the saga's best closing move or its most evasive one, depending on who you ask. This site's view is that it is both.
Canon and Legends
There is no Legends version of this era, because the Legends post-Endor storyline stopped in 2013 and the continuity was retired in April 2014, having gone in an entirely different direction from the same starting point. The Legends future is on the Legacy Era page. Reading the two branches against each other is the most interesting thing you can do with the post-Endor shelf: two continuations of the same 4 ABY, one built by a novel programme over twenty years and one by three films.
What comes after
Lucasfilm's ninth and final publishing era, The New Jedi Order, begins after the Battle of Exegol and covers the galaxy Rey inherits. It is at present nearly empty of published fiction, and this site will not fill it with speculation. Note that its name is borrowed from the 1999–2003 Legends series covered on a separate page; the two have nothing in common but the words.