User blog comment:Void Samukai/The 7 key BBs in history/@comment-14850713-20160120073340

Khoi, as you are being technical about the term battleship (or line-of-battle ship), then HMS Warrior shouldn't count as she was classified as an armored frigate (remember, there were still wooden ship-of-the-line that served side-by-side with her). Still, I consider her one of the key early ironclads. I say "one of" because she wasn't the first. The RN was only a technological follower then, but they would build on the pioneering tech to come up with a better design. So the pioneering ironclad ("key' by your definition) should be French Gloire. As for my full list:

1. Mary Rose - same reason

2. Le Napoleon - the first steam-powered ship-of-the-line; from then on ships-of-the-line were built with steam-power or fitted with auxiliary engines

3. Gloire - first sea-going ironclad

4. Redoutable - first steel battleship; with steel replacing iron, battleship sizes started to grow considerably

5. HMS Devastation - not the first to get rid of sails, but the first to standardize fore and aft main guns; considered the first of the pre-dreadnoughts

6. HMS Dreadnought - same reason

7. USS South Carolina - first with super-firing main guns which became the standard template of main gun arrangement for all battleships up to Yamato; (she was actually designed before Dreadnought so I wonder how battleships of this era would've been called if she had been commissioned first -- South Carolina-type, pre-''South...?)

Runners-up (not in chronological order)

8. USS Nevada, for "all-or-nothing" armor, which was adopted to varying degrees (though in practice, no structural part of a ship was totally unarmored, so no part had "nothing" thus kicking her out of my Top 7)

9. Iowa-class - the pinnacle of the fast battleship, their subsequent modernization and use as land-attack platforms, and their effectiveness in this role, made sure that the fire mission will always be a key requirement for the US Navy (leading to the development of the Zumwalt-class) not to mention encouraging the constant imaginings of some professional and amateur naval enthusiasts (like us) that battleships may yet be resurrected in the future