If you're using Vuex you can use https://github.com/vuejs/vuex-router-sync
Just initialize it in your main file with:
import VuexRouterSync from 'vuex-router-sync';
VuexRouterSync.sync(store, router);
Each route change will update route state object in Vuex.
You can next create getter to use the from Object in route state or just use the state (better is to use getters, but it's other story
https://vuex.vuejs.org/en/getters.html),
so in short it would be (inside components methods/values):
this.$store.state.route.from.fullPath
You can also just place it in <router-link> component:
<router-link :to="{ path: $store.state.route.from.fullPath }">
Back
</router-link>
So when you use code above, link to previous path would be dynamically generated.