Who is Baron Arminio Piovasco di Rondo from The Baron in the Trees and what is their importance?

Cosimo's father, Arminio Piovasco di Rondo, is a man unable to wrap his mind around the changes that come about as a result of the Wars of Succession, and hopes always to see his land-owning status as Duke of Ombrosa restored and passed along to Cosimo, whom he doggedly trains for a nobleman's life. He is a bore to his sons due to his singularity of purpose, and because nothing they are or which interests them is as important to him as his own out-of-date set of hopeless priorities. A bit of reconciliation comes into his relationship with Cosimo when, after Cosimo's organization of the people in the village to protect the trees against fire, he visits and gives him his sword. It is an acknowledgement that Cosimo is behaving nobly, even if in a less illustrious realm than Arminio would have liked.