A 'fighting spirit' fights instead of the one summoning and controlling it, and may be visible or invisible but have.some connection to the user.
In X-Men Apocalypse (2016), before Jean Grey attacks Apocalypse, she releases a fire bird aura.
In My Hero Academia (2014) Tokoyami Fukage can create a black bird around him who fights in his behalf.
In Naruto (1999), Sasuke and other uchihas can create a giant samurai-like warrior around them who protects them and fights for them.
And in Jojo's Bizarre Adventure: Stardust Crusaders (1989), certain humans can create "stands", which are 'personifications' of 'life energy' whose abilities are given visual form and fight for them.
But which was the first story to feature a fighting spirit?