Sotah 8:7 says that for obligatory wars all go out to fight, "even a bridegroom from his chamber and a bride from her canopy". Historically, was this in fact our practice? Did women participate in the conquest of the land (which Rabbi Yehudah says was an obligatory war) or in defending it before we were conquered and the temples destroyed? Did women fight alongside the men, or did they participate in ways that didn't involve fighting directly? It sounds like at least some of the women of Reuven and Gad stayed home during the conquest of the land.
If they fought, (how) were they trained?
I do know that Devorah not only fought but led troops, but as a prophetess she might have had special circumstances.