My bad- I had a Japanese 360 and didn't realize it never got localized. It does look like there's a patched English version floating around to use on modded systems at least.
There's a number of ports like this they never released in English, for whatever reason, particularly on PS3, PSP, and Vita. Samurai Warriors 2 got a nice HD port to PS3 and Vita which contains 2, XL, and Empires all together. Samurai Warriors 3Z on PS3 was a lot better than the Wii version (although that one can possibly be explained by Nintendo having some kind of exclusive on it on Wii) and then there's Warriors Orochi Z on PS3, which contains HD ports of WO1 and WO2 with some new content, to name a few.
The Switch also got several releases that were never localized. I have the Warriors Orochi 3 Ultimate and Samurai Warriors 4 DX ports and they are really, really awesome -all the DLC was included and they run GREAT- still wish they got English versions, but at least WO3U finally hit Steam and works on the Deck.