Land issue

Our property has been under my great grandfather and then grandfather and we have records of the same from 1936. My grandfather allowed one of his employees, who also happens to be a distinct relative to stay in the house(with a letter etc stating that the relative would vacate when asked to do so). The relative later also wrote that he will vacate and asked for sometime etc. my grandfather put a case against him and got a decree in his favour. Subsiquently he passed away without leaving a will. My father and grandfather were not in talking terms and when we went to the town this guy living in this house showed us some of our other properties and got some brownie points from my father and finally told him that some case was going on and requested him to take it back. My dad didn't get into too much detail and went for an out of court settlement(papers of which Im trying to get). My father's verbal terms were build something small there and stay for the time being. This guy has built a huge mansion and now I need the place and he is not vacating and when I asked a common person to put a word. He said " I will not move from here and ask them to go and see out of court settlement". This really upset me and I was wondering what I could do. Though I'm moving legally I wanted a 2nd legal opinion. When my father gave the anscestral property both me and my brother were majors if that helps. I'm ok with my dad giving off te property but that guy acting like that is very hurting and I want to get him out of the property. Pls help.