Henry VI, Part 2 is set during the English Wars of the Roses. This play dramatizes the York vs. Lancaster (Henry's side) debate that begins in Henry VI, Part 1, after Henry Bolingbroke (a Lancaster) has usurped the throne from Richard II (a York).
From a historical standpoint, this was all going down in the 15th century. Shakespeare makes it seem like the events all happened one after the other, but in reality, they were spread out over many years. The play ends with York making his way to London to bump Henry off the throne, and this paves the way for the action in Henry VI, Part 3.
We stay in England in this play, mainly hanging out in London, St. Edmund's, Kent, and St. Albans. Sure, there's a quick trip to York's and Gloucester's homes, and there's a lot of talk about some French lands being lost, but we stay pretty local for most of the play. Maybe Shakespeare was trying to show us that all of these nobles are in the same country. Foreigners might be the enemy in other plays, but in this war, it's England fighting England, and no one has the hometown advantage.