>>111655338It all depends on if you are going to go out and buy a physical trade/HC, or just pirate stuff.
An easy start is with the contents of the "Superboy and the Legion of Super-Heroes" HC. There's two of those, and they collect material from when Levitz started writing the original (but adult) LoSH in the 1970s. So, early bronze age stuff. This wikipedia page is pretty useful.
https://en.wikipedia.org/wiki/List_of_Legion_of_Super-Heroes_publicationsSo if you see from that page, the book titled "Superboy" became "Superboy and the LoSH" until issue #259. With that issue, Superboy was dropped from the book and was renamed Legion of Super-Heroes (vol 2, because vol 1 was a couple reprints of older stories).
Volume 2 ran until issue 313 in around 1984. Volume 3 ran until 1989, and that's when stuff started to get fucky. CoIE had sort of fucked them in 1985-6, so don't expect any Superboy or Superman anymore (outside of a half-assed explanation for why Superboy used to be with them despite Byrne rebooted Supes and decided that he was never Superboy).
Volume 4 featured a timeskip five years into the future, and is the absolute worst place to start. You won't know who anyone is, or why you should be shocked by what happened to everyone. With lowering sales and bad stories, DC decided to use Zero Hour in 1994 to reboot them.
If you want to read the Reboot Legion (which is generally characterized as being more lighthearted, but I don't really agree), you can pick up the two Legionnaires trades (or rips). Reboot LoSH is a bit of a pain in the ass to read because it was two books that acted like a twice monthly one. So read Legionnaires #30, then LoSH vol 4 #73, then Legionnaires #31, etc etc
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