This volume compiled individual issues of The Avengers comics issued from August 1966 through May 1967.
Just like the early Justice League comics excluded Batman and Superman from most stories, Avengers comics of this time period excluded Iron Man and Thor. The roster included Captain America, Hawkeye, Goliath, the Wasp, Quicksilver, and the Scarlet Witch. The Black Widow appeared in a couple of issues, but she wasn’t a member yet. Hercules began his stay with the Avengers during this time period, as Zeus exiled him from Olympus for one year, but at this point he was not awarded membership in the group.
Comics from this time period are a bit problematic for me, as they usually include a lot more dialogue than modern comics do, which results in longer reading time. The characters aren’t as nuanced as they are in today’s books, and the plots are generally more simplistic. I still enjoy reading comics from this time period for their nostalgic value, though, since I first started reading comics around this time.