The Early Golden Age is the period between the release of Flash Comics 1, January 1940, and the summer of 1944, when a reduction in page size saw the end to a number of strips.
While the previous era, the Dawn of Comics, had seen a variety of styles experimented with, in this era, super-heroes have won the game. These four year would see the creation of almost all the classic heroes from the Golden Age.
It would also see the emergence of an entirely new conception in fiction, the super-hero team.
I will start by going through the stories of the series that began in the previous era, so beginning with Barry O'Neill, the longest-running strip at the time. Once I have caught up (with Gary Concord, Ultra-Man), I will proceed through the various series that launched in this era.
One curious note. While this period saw the emergence of the classic Golden Age heroes, many of the classic Golden Age villains do not make their debut yet. They have to wait for the Late Golden Age.