Finding and using companions on map?

[Seipher09]

I am getting ready to attack my first castle and I have a companion who is leading 60 troops. How do I find my companion on the map and how do I get them along with the assigned troops to attack the castle with me?

 

[MacarioTheClown]

You want to form an army through the Kingdom menu and invite them (for 0 influence). If you aren't high enough clan rank to form armies yet, you won't be able to.